Answer:
The way adolescents spend their time can strongly influence their health later in life. For youth to maintain a healthy future, they need plenty of sleep; good nutrition; regular exercise; and time to form relationships with family, friends, and caring adults. Additionally, the time adolescents spend in school and in after-school activities with peers and adults can advance healthy academic, emotional, social, and physical development. The amount of time they spend on screens and in social media may also influence adolescents’ overall well-being.
The American Time Use Survey, collected by the U.S. Bureau of Labor Statistics, contains detailed information about how individuals ages 15 and older use their time and provides a picture of a typical weekday and weekend day for a high school teen during the school year. Here we specifically analyze how adolescents ages 15-19 who are enrolled in high school spend their time.
Step-by-step explanation:
Company A makes a large shipment to Company B. Company B can reject the shipment if they can conclude that the proportion of defective items in the shipment is larger than 0.1. In a sample of 400 items from the shipment, Company B finds that 59 are defective. Conduct the appropriate hypothesis test for Company B using a 0.05 level of significance.
Answer:
[tex]z=\frac{0.1475-0.1}{\sqrt{\frac{0.1(1-0.1)}{400}}}=3.17[/tex]
The p value for this case would be given by:
[tex]p_v =P(z>3.17)=0.00076[/tex]
For this case the p value is lower than the significance level so then we have enough evidence to reject the null hypothesis and we can conclude that the true mean is significantly higher than 0.1 and then Company B can reject the shipment
Step-by-step explanation:
Information provided
n=400 represent the random sample taken
X=59 represent number of defectives from the company B
[tex]\hat p=\frac{59}{400}=0.1475[/tex] estimated proportion of defectives from the company B
[tex]p_o=0.1[/tex] is the value to verify
[tex]\alpha=0.05[/tex] represent the significance level
z would represent the statistic
[tex]p_v[/tex] represent the p value
Hypothesis to test
We want to verify if the true proportion of defectives is higher than 0.1 then the system of hypothesis are.:
Null hypothesis:[tex]p \leq 0.1[/tex]
Alternative hypothesis:[tex]p > 0.1[/tex]
The statistic would be given by:
[tex]z=\frac{\hat p -p_o}{\sqrt{\frac{p_o (1-p_o)}{n}}}[/tex] (1)
Replacing the info given we got:
[tex]z=\frac{0.1475-0.1}{\sqrt{\frac{0.1(1-0.1)}{400}}}=3.17[/tex]
The p value for this case would be given by:
[tex]p_v =P(z>3.17)=0.00076[/tex]
For this case the p value is lower than the significance level so then we have enough evidence to reject the null hypothesis and we can conclude that the true mean is significantly higher than 0.1 and then Company B can reject the shipment
Translate to a system of equations: Twice a number plus three times a second number is negative one. The first number plus four times the second number is two.
Answer:
work is shown and pictured
For the given central angle, determine the distance traveled along the unit circle from the point (1, 0). 210 degrees a. 3.67 units c. 1.83 units b. 1.17 units clockwise d. 7.33 units
Answer:
3.67 units
Step-by-step explanation:
The central angle is at the point (0,0).
Then it's at the point (1,0)
Then it moved 210 degrees.
Let's bear in mind that we start moving the degree from it's current position.
So moving 210 degrees is moving 180 degrees plus 30 degrees.
Moving 180 degrees I like transforming linearly.
Now the location is at (-1,0)
But the distance covered will be
= 2πr*210/360
r = 1
= 2*3.142*1*(210/360)
= 6.144*0.5833333
= 3.67 units
Please help me with this problem I'm lost
Answer:
24
Step-by-step explanation:
Multiple (4)(2)= 8
-3(8) =24
Please help. I’ll mark you as brainliest if correct!
Answer:
(0. 4)
(-2, 0)
Step-by-step explanation:
The y- coordinates (output) at the highest and lowest points are called the absolute maximum and absolute minimum, respectively.As per given graph,
absolute maximum is 4, point (0, 4)absolute minimum is 0, point (-2, 0)One-third times the difference of a number and 5 is
Which equation best shows this?
3
One possible first step in solving the equation in the above problem is to
The value of the number is
Answer:
the value of x is 3
Step-by-step explanation:
Hope this helps!!!! :)
Answer:
one is a
two is c
three is b
Step-by-step explanation:
If (x + k) is a factor of f(x), which of the following must be true?
f(K) = 0
fl-k)=0
A root of f(x) is x = k.
A y intercept of f(x) is x = -k.
Answer:
f(-k)=0Step-by-step explanation:
(x + k) is a factor of f(x)
x+k=0 => x= -k; -k is a root of f(x)
=> f(-k)=0
[tex](x + k) is a factor of f(x)x+k=0 = > x= -k; -k is a root of f(x)= > f(-k)=0[/tex]
So the correct option is B.fl-k)=0.
What is a root function example?
The cube root function is f(x)=3√x f ( x ) = x 3 . A radical function is a function that is defined by a radical expression. The following are examples of rational functions: f(x)=√2x4−5 f ( x ) = 2 x 4 − 5 ; g(x)=3√4x−7 g ( x ) = 4 x − 7 3 ; h(x)=7√−8x2+4 h ( x ) = − 8 x 2 + 4 7 .
What is the root function?
The root function is used to find a single solution to a single function with a single unknown. In later sections, we will discuss finding all the solutions to a polynomial function. We will also discuss solving multiple equations with multiple unknowns. For now, we will focus on using the root function.
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The manager of the motor pool wants to know if it costs more to maintain cars that are driven more often. Data are gathered on each car in the motor pool regarding number of miles driven (X) in a given year and maintenance costs for that year (Y) in thousands of dollars. The regression equation is computed as: Y-60+0.08X, and the p-value for the slope estimate is 0.7. What conclusion can we draw from this study? a. Cars that are driven more tend to cost more to maintain. b. There's no statistically significant linear relationship between the number of miles driven and the maintenance cost c. The correlation between the response variable and independent variable is significant. d. The slope estimate is significantly different from zero.
Answer:
b. There's no statistically significant linear relationship between the number of miles driven and the maintenance cost
Step-by-step explanation:
The p-value for the slope estimate show us how strong is the certainty that there are a linear relationship between both variables. In this case, the p-value for the slopes shows if there is a significant relationship between the number of miles driven and the maintenance cost.
If we have a high p-value like 0.7 we can said that there is no certainty in the linear relationship. it means that there's no statistically significant linear relationship between the number of miles driven and the maintenance cost.
The given line segment passes through the points (0, -3) and (-5, -4).
What is the equation of the line that is parallel to the given line and passes through the point (-2, 2)?
Answer:
y= 1/5x + 12/5
Step-by-step explanation:
Points: (0, -3) and (-5, -4)Line: y= mx+bSlope: m=(y2-y1)/(x2-x1)= (-4+3)/(-5-0)= -1/-5= 1/5Y-intercept: -3= 0*1/5+b ⇒ b= -3So the line is: y= 1/5x - 3Parallel line to this has same slope and passes through the point (-2, 2)
Its y- intercept is: 2= 1/5(-2)+b ⇒ b= 2+2/5= 12/5The required equation in slope- intercept form is:
y= 1/5x + 12/5To solve a polynomial inequality, we factor the polynomial
into irreducible factors and find all the real_______polynomial. Then we find the intervals determined by the real__________sign of the polynomial on that interval. Let
$$P(x)=x(x+2)(x-1)$$
Fill in the diagram to find the intervals on which
$P(x) \geq 0$
we see that $P(x) \geq 0$ on the
intervals_______and________.
Answer:
To solve a polynomial inequality, we factor the polynomial into irreducible factors and find all the real _zeros_ polynomial. Then we find the intervals determined by the real _zeros and use test points in each interval to find the_ sign of the polynomial on that interval.
If P(x) = x(x+2)(x-1)
And P(x) ≥ 0
We see that P(x) ≥ 0 on the intervals (-2, 0) and (1, ∞).
Step-by-step explanation:
The complete question is attached to this solution
To solve inequality of a polynomial, we first obtain the solutions of the polynomial. The solutions of the polynomial are called the zeros of the polynomial.
If P(x) = x(x+2)(x-1)
The solutions of this polynomial, that is the zeros of this polynomial are 0, -2 and 1.
To now solve the inequality that arises when
P(x) ≥ 0
We redraw the table and examine the intervals
The intervals to be examined as obtained from the zeros include (-∞, -2), (-2, 0), (0, 1) and (1, ∞)
Sign of | x<-2 | -2<x<0 | 0<x<1 | x>1
x | -ve | -ve | +ve | +ve
(x + 2) | -ve | +ve | +ve | +ve
(x - 1) | -ve | -ve | -ve | +ve
x(x+2)(x-1) | -ve | +ve | -ve | +ve
The intervals that satisfy the polynomial inequality P(x) = x(x+2)(x-1) ≥ 0 include
(-2, 0) and (1, ∞)
Hope this Helps!!!
On a piece of paper, graph fx) = 2• (0.5)*. Then determine which answer choice matches the graph you drew.
Answer:
Graph A
Step-by-step explanation:
The common ratio is less than 1, so the graph will be decreasing. The initial value is 2, so the y-intercept will be 2. Graph A fits this criteria.
I hope this helps :))
The graph A is correct.
What is a graph?A diagram (such as a series of one or more points, lines, line segments, curves, or areas) that represents the variation of a variable in comparison with that of one or more other variables.
The equation is,
[tex]y=2(0.5)^{x}[/tex]
Plotting the graph, we get,
Option A
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If p(x) = 2x2 - 4x and q(x) = x - 3, what is (pºq)(x)?
Answer:
Step-by-step explanation:
p(x)=2x^2
q(x)=x-3
(p•q)(x)=2(x-3)^2
2(x^2-6x+9)
2x^2-12x+18
On the map, Seattle, Portland, and Boise form a triangle whose sides are shown in the figure below. If the actual distance from Seattle to Boise is 400 miles, find the distance from Seattle to Portland.
Answer:
150 miles
Step-by-step explanation:
If the distance between Seattle and Boise is 400 miles and the image illustrates 4", then there must be a proportionate between the two values. Therefore, if the distance between Seattle and Portland is 1.5", then the real distance must be 150 miles.
An HP laser printer is advertised to print text documents at a speed of 18 ppm (pages per minute). The manufacturer tells you that the printing speed is actually a Normal random variable with a mean of 17.35 ppm and a standard deviation of 3.25 ppm. Suppose that you draw a random sample of 10 printers.
Required:
a. Using the information about the distribution of the printing speeds given by the manufacturer, find the probability that the mean printing speed of the sample is greater than 17.55 ppm.
b. Use normal approximation to find the probability that more than 48.6% of the sampled printers operate at the advertised speed (i.e. the printing speed is equal to or greater than 18 ppm)
Answer:
a) The probability that the mean printing speed of the sample is greater than 17.55 ppm = 0.4247
b) The probability that more than 48.6% of the sampled printers operate at the advertised speed = 0.4197
Step-by-step explanation:
The central limit theorem explains that for an independent random sample, the mean of the sampling distribution is approximately equal to the population mean and the standard deviation of the distribution of sample is given as
σₓ = (σ/√n)
where σ = population standard deviation
n = sample size
So,
Mean of the distribution of samples = population mean
μₓ = μ = 17.35 ppm
σₓ = (σ/√n) = (3.25/√10) = 1.028 ppm
a) The probability that the mean printing speed of the sample is greater than 17.55 ppm.
P(x > 17 55)
We first normalize 17.55 ppm
The standardized score for any value is the value minus the mean then divided by the standard deviation.
z = (x - μ)/σ = (17.55 - 17.35)/1.028 = 0.19
To determine the required probability
P(x > 17.55) = P(z > 0.19)
We'll use data from the normal probability table for these probabilities
P(x > 17.55) = P(z > 0.19) = 1 - P(z ≤ 0.19)
= 1 - 0.57535 = 0.42465 = 0.4247
b) The probability that more than 48.6% of the sampled printers operate at the advertised speed
We first find the probability that one randomly selected printer operates at the advertised speed.
Mean = 17.35 ppm
Standard deviation = 3.25 ppm
Advertised speed = 18 ppm
Required probability = P(x ≥ 18)
We standardize 18 ppm
z = (x - μ)/σ = (18 - 17.35)/3.25 = 0.20
To determine the required probability
P(x ≥ 18) = P(z ≥ 0.20)
We'll use data from the normal probability table for these probabilities
P(x ≥ 18) = P(z ≥ 0.20) = 1 - P(z < 0.20)
= 1 - 0.57926 = 0.42074
48.6% of the sample = 48.6% × 10 = 4.86
Greater than 4.86 printers out of 10 includes 5 upwards.
Probability that one printer operates at advertised speed = 0.42074
Probability that one printer does not operate at advertised speed = 1 - 0.42074 = 0.57926
probability that more than 48.6% of the sampled printers operate at the advertised speed will be obtained using binomial distribution formula since a binomial experiment is one in which the probability of success doesn't change with every run or number of trials. It usually consists of a number of runs/trials with only two possible outcomes, a success or a failure. The outcome of each trial/run of a binomial experiment is independent of one another.
Binomial distribution function is represented by
P(X = x) = ⁿCₓ pˣ qⁿ⁻ˣ
n = total number of sample spaces = 10
x = Number of successes required = greater than 4.86, that is, 5, 6, 7, 8, 9 and 10
p = probability of success = 0.42074
q = probability of failure = 0.57926
P(X > 4.86) = P(X ≥ 5) = P(X=5) + P(X=6) + P(X=7) + P(X=8) + P(X=9) + P(X=10) = 0.4196798909 = 0.4197
Hope this Helps!!!
8. Peter and his partner are conducting a physics experiment on pendulum motion. Their 30-cm
pendulur traverses an arc of 15 cm. To the nearest degree, how many degrees of rotation did
the pendulum swing?
Answer: 90/pi degrees
Step-by-step explanation:
It forms a 15cm arc from a circle of radius 30 cm.
The diameter is 30*2*pi = 60pi cm. So the arc is 15/60pi = 1/4pi of the way around a 360 degree circle. This is 1/4pi * 360 = 90/pi degrees.
Hope that helped,
-sirswagger21
The pendulum will swing 28.68° if the 30-cm pendulum traverses an arc of 15 cm.
What is a circle?It is defined as the combination of points that, and every point has an equal distance from a fixed point (called the center of a circle).
We know that relationship between arc length s and central angle θ:
s = rθ
Where r is the radius of the circle
We have s = 15 cm
r = 30 cm
15 = (30)(θ)
θ = 0.5 radians
To convert it to a degree, multiply it by 180/π
θ = 0.5(180/π)
θ = 28.647 ≈ 28.68°
Thus, the pendulum will swing 28.68° if the 30-cm pendulum traverses an arc of 15 cm.
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If a⊕ b= 1/a + 1/b , for what decimal value of a is a⊕ 0.2=10?
Answer:
0.2
Step-by-step explanation:
1/0.2 = 5
10-5 = 5
1/a = 5
a = 1/5
a = 0.2
Answer:1/5 or 0.2
Step-by-step explanation:
1/a+1/0.2=10
1/a+1/2/10=10
1/a=10/2=10
1/a+5=10
1/a=10-5
1/a=5
a=1/5 or 0.2
A company that manufactures video cameras produces a basic model and a deluxe model. Over the past year, 41% of the cameras sold have been of the basic model. Of those buying the basic model, 31% purchase an extended warranty, whereas 48% of all deluxe purchasers do so. If you learn that a randomly selected purchaser has an extended warranty, how likely is it that he or she has a basic model
Answer:
[tex]75.6\%[/tex]
Step-by-step explanation:
Let B be the event of buying a basic model.
Given that P(B) = 41%
Let D be the event of buying a basic model.
Given that P(D) = 1 - 41% = 59%
Let E be the event of extended warranty.
Given that:
P(E [tex]\cap[/tex] B) = 31% and
P(E [tex]\cap[/tex] D) = 48%
P(E) = P(E [tex]\cap[/tex] B) [tex]\times[/tex] P(B) + P(E [tex]\cap[/tex] D) [tex]\times[/tex] P(D)
P(E) = 31% [tex]\times[/tex] 41% + 48% [tex]\times[/tex] 59% = 0.4103
To find: P(B/E)
Formula:
[tex]P(B/E) = \dfrac{P(E \cap B)}{P(E)}[/tex]
[tex]\Rightarrow \dfrac{0.31}{0.41}\\\Rightarrow 0.756\\\Rightarrow 75.6\%[/tex]
So, the correct answer is [tex]75.6\%[/tex].
Select the correct answer. Meg deposited a $3,000 bonus check in a new savings account. The account has an interest rate of 3% for 5 years. The interest is compounded daily. How much money did Meg have at the end of the account term? (Round your answer to the nearest dollar.)
Answer:
$3,485.48
Step-by-step explanation:
For computing the money required at the end of the account term we need to apply the Future value formula i.e be to shown in the attachment below:
Given that,
Present value = $3,000
Rate of interest = 3% ÷ 365 days = 0.00821917
NPER = 5 years × 365 days = 1,825
PMT = $0
The formula is shown below:
= FV(Rate;NPER;PMT;PV;type)
So, after applying the above formula
the amount of future value is $3,485.48
determine whether the forces in the pair are pulling at right angles to each other for the values. a-3.4 and b=2.6, which are legs of a right triangle, find c, the hypotenuse, to the nearest tenth
Answer:
4.3 units
Step-by-step explanation:
In this question we use the Pythagorean Theorem which is shown below:
Data are given in the question
Right angle
a = 3.4
b = 2.6
These two are legs of the right triangle
Based on the above information
As we know that
Pythagorean Theorem is
[tex]a^2 + b^2 = c^2[/tex]
So,
[tex]= (3.4)^2 + (2.6)^2[/tex]
= 11.56 + 6.76
= 18.32
That means
[tex]c^2 = 18.56[/tex]
So, the c = 4.3 units
Here is rectangle A. Block A. Rectangle B is ¹/₅ longer than A Block B. Rectangle C is ¹/₃ longer than B Block C. The total length of all three rectangles is 133 cm. How much longer is rectangle C than B?
Answer:
Rectangle C is 14 cm longer than B
Step-by-step explanation:
Let x be the length of Rectangle A. Rectangle B is ¹/₅ longer than A Block B,
Therefore the length of rectangle B is:
[tex]x+\frac{1}{5}x[/tex]
Rectangle C is ¹/₃ longer than B, therefore the length of rectangle c is:
[tex]x+\frac{1}{5}x+\frac{1}{3}(x+\frac{1}{5}x) =x+ \frac{1}{5}x+\frac{1}{3}x+\frac{1}{15}x=x+\frac{9}{15}x[/tex]
The total length of all three rectangles is 133 cm.
Length of rectangle A + Length of rectangle B + Length of rectangle C = 133 cm
[tex]x+x+\frac{1}{5}x +x+\frac{9}{15}x=133\\x+x+x+\frac{1}{5}x +\frac{9}{15}x=133\\3x+\frac{12}{15}x=133\\ 45x+12x=1995\\57x=1995\\x=35cm[/tex]
Therefore the length of rectangle A is 35 cm, the length of rectangle B is [tex]35+\frac{1}{5}*35=42\ cm[/tex] and the length of rectangle C is [tex]35+\frac{9}{15}*35=56\ cm[/tex]
Rectangle C is ¹/₃ longer than B, which is 14 cm (42\3) longer than B
A parabola has a focus of (6,–6) and a directrix of y = –2. Which of the following could be the equation of the parabola?
Answer:
[tex]-8(y+4) =(x-6)^{2}[/tex]
Step-by-step explanation:
The standard form of a parabola is given by the following equation:
[tex](x-h)^{2} =4p(y-k)[/tex]
Where the focus is given by:
[tex]F(h,k+p)[/tex]
The vertex is:
[tex]V=(h,k)[/tex]
And the directrix is:
[tex]y-k+p=0[/tex]
Now, using the previous equations and the information provided by the problem, let's find the equation of the parabola.
If the focus is (-6,6):
[tex]F=(h,k+p)=(6,-6)[/tex]
Hence:
[tex]h=6\\\\k+p=-6\hspace{10}(1)[/tex]
And if the directrix is [tex]y=-2[/tex] :
[tex]-2-k+p=0\\\\k-p=-2\hspace{10}(2)[/tex]
Using (1) and (2) we can build a 2x2 system of equations:
[tex]k+p=-6\hspace{10}(1)\\k-p=-2\hspace{10}(2)[/tex]
Using elimination method:
(1)+(2)
[tex]k+p+k-p=-6+(-2)\\\\2k=-8\\\\k=-\frac{8}{2}=-4\hspace{10}(3)[/tex]
Replacing (3) into (1):
[tex]-4+p=-6\\\\p=-6+4\\\\p=-2[/tex]
Therefore:
[tex](x-6)^{2} =4(-2)(y-(-4)) \\\\(x-6)^{2} =-8(y+4)[/tex]
So, the correct answer is:
Option 3
What’s the correct answer for this?
Answer:
D
Step-by-step explanation:
Length × Width = Area
So we'll substitute the Area of the circle having formula, πr²
please help me explain your answer only answer if you are sure
Answer:
The answer of top prism is 262
and down prism is 478
The upper figure is triangular prism.
so, we use bh+2ls+lb formula
B=5
h=3
s=4
l=19
Now,
surface area of triangular prism = bh+2ls+lb
= 5×3+2×19×4+19×5
= 262
The down figure is rectangular prism.
so, we use 2lw+2lh+2hw
l=5
h=6
w=19
Now,
The area of rectangular prism = 2lw+2lh+2hw
= 2×5×19+2×19×6+2×5×6
= 478
The results of a linear regression are shown below.
y= ax + b
a = -1.15785
b= 139.3171772
r= -0.896557832
r2 = 0.8038159461
Which phrase best describes the relationship between x and y?
1)Strong Postive Correlation
2)Strong Negative Correlation
3)Weak Positive Correlation
4)Weak Negative Correlation
Answer:
2) Strong Negative Correlation
Step-by-step explanation:
With the value of r we have both the information about the sign of the relationship and the strength of this relationship.
As the value of r is negative, we can conclude that the correlation between x and y is negative.
Also, as the absolute value of r is close to 1, we can conclude that this relationship is strong.
The strength can also be seen in the value of r2, which is also close to 1, but this value does not give information about the sign.
The value of the slope a, being negative, can also tell us that the relation between x and y is a negative correlation.
Please help. I’ll mark you as brainliest if correct!!!!
Answer:
a= 2/5
b= -3/5
Step-by-step explanation:
We need to multiply the numerator and denominator by -i (conjugate) to cancel out i in the denominator
[tex]\frac{(3+2i)(-i)}{5i(-i)}[/tex]
This simplifies to:
[tex]\frac{-3i+-2i^{2} }{-5i^{2} }[/tex]
This further simplifies to:
[tex]\frac{-3i +2}{5}[/tex]
Can be rewritten as:
[tex]\frac{2}{5} +-\frac{3}{5} i[/tex]
a = 2/5
b = -3/5
Identify the lower class limits, upper class limits, class width, class midpoints, and class boundaries for the given frequency distribution. Also identify the number of individuals included in the summary.
Age (yr) when award was won:
20-24
25-29
30-34
35-39
40-44
45-49
50-54
Frequency:
29
36
15
3
6
2
2
Answer:
Lower class Limit: 20,25,30,35,40,45,50
Upper class limit: 24,29,34,39,44,49,54
Class width: 4
Class Midpoints : 22,27,32,37,42,47,52
Class Boundries : 19.5,24.5,29.5,34,5,39.5,44.5,49.5,54.5
Total Individuals: 93
Step-by-step explanation:
Lower class limit is the lowest value of a class e.g in the first class, the lowest value is 20. Similarly find lower class limit of othere classes.
Upper class limit is the highest value of a class e.g in the first class, the highest value is 24. Similarly find upper class limit of othere classes.
Class width is the difference between highest and lowest value of a class e.g 24-20=4
Class Midpoints can be found by adding lowest and highest value of a class and dividing it by 2 e.g (20+24)/2 = 22
Class boundaries are the halfway point which seperates the classes e.g for first classes, clasee boundry is (19.5,24.5)
Total individuals are founf by adding all the frequencies.
I need help with this one
Answer:
2 2/3
Step-by-step explanation:
Cheeseburgers to go has advertised for counter help. If you take the job, you will be working 18 hours
a week for $69.20 per week. How much would you make an hour?
Answer:
about $3.84
Step-by-step explanation:
you do 69.20 divided by 18
Assume that 1100 births are randomly selected and exactly 556 of the births are girls. Use subjective judgment to determine whether the given outcome is unlikely, and also determine whether it is unusual in the sense that the result is far from what is typically expected.
Answer:
The sample proportion for the births that are girls is 0.505. It is slightly higher than the expected value of 0.5, but the right way to answer if it is an unusual proportion is by performing an hypothesis test.
The hypothesis test results in not enough evidence to claim that the outcome is unlikely. This sample result has a probability of 0.7627 of appearing by pure chance in a population with proportion p=0.5.
Step-by-step explanation:
This is a hypothesis test for a proportion.
The claim is that the proportion of girls birth differs significantly from the expected proportion (50%).
Then, the null and alternative hypothesis are:
[tex]H_0: \pi=0.5\\\\H_a:\pi\neq 0.5[/tex]
The significance level is 0.05.
The sample has a size n=1100.
The sample proportion is p=0.505.
p=X/n=556/1100=0.505
The standard error of the proportion is:
[tex]\sigma_p=\sqrt{\dfrac{\pi(1-\pi)}{n}}=\sqrt{\dfrac{0.5*0.5}{1100}}\\\\\\ \sigma_p=\sqrt{0.000227}=0.015[/tex]
Then, we can calculate the z-statistic as:
[tex]z=\dfrac{p-\pi-0.5/n}{\sigma_p}=\dfrac{0.505-0.5-0.5/1100}{0.015}=\dfrac{0.005}{0.015}=0.302[/tex]
This test is a two-tailed test, so the P-value for this test is calculated as:
[tex]\text{P-value}=2\cdot P(z>0.302)=0.7627[/tex]
As the P-value (0.7627) is greater than the significance level (0.05), the effect is not significant.
The null hypothesis failed to be rejected.
There is not enough evidence to support the claim that the proportion of girls birth differs significantly from the expected proportion (50%).
Tricia has a birthday party. During the party, she opened 36 gifts, which was 60% of all her gifts. After the party, she opened the rest of the gifts and found that 25% of them were the same present, so she returned all but one of the duplicate gifts. How many gifts did she return?
Answer:
She returned 5 gifts.
Step-by-step explanation:
36 gifts is 60% = 0.6 of all the gifts that she received. How many presents are 100% = 1?
36 gifts - 0.6
x gifts - 1
0.6x = 36
x = 36/0.6
x = 60
She received 60 gifts.
She opened the rest of the gifts and found that 25% of them were the same present
The rest is 60 - 36 = 24 gifts.
25% is (1/4)*24 = 6 duplicate figts
She returned all but one of the duplicate gifts.
That is, she returned 6 - 1 = 5 gifts.