Answer:
57
Step-by-step explanation:
Given that :
Standard deviation (σ) = 5 minutes = (5 *60) = 300 seconds
Margin of Error, E = 78
Assume a confidence interval of 95%;
Using the relation :
((Zα/2 * σ) / E)²
(1 - α)/2 = (1 - 0.95)/2 = 0.05 /2 = 0.025
Z0.025 = 1.96
Sample size = ((1.96 * 300) / 78)²
Sample size = (588 / 78)^2
Sample size = 7.5384615^2
Sample size = 56.828
= 57 samples
6) A garden measures p metres by 3p + 2 metres.
a) Write an expression that describes the perimeter of the garden.
b) The garden has a perimeter of 76 metres. Write an equation to show this.
c) Solve your equation to find the value of p.
ALL WORKING OUT NEEDED
p = 18.5
Step-by-step explanation:
a. to find perimeter you have to add all the sides together
So if one side is p, and the other side is 3p+2, just add them together like this
p + 3p + 2, then combine the ps so the expression is
4p + 2
b. now you find out the perimeter is 76
So put the original expression of your perimeter and 76 together like this
4p + 2 = 76
c. So now solve the equation
4p + 2 = 76
subtract 2 from both sides to get the ps alone
4p = 74
now divide by 4 to get the p by itself
74 ÷ 4 is 18.5, or 18 1/2
So p = 18.5 or 18 1/2
I need help ASAP, marking brainliest!
61% of x algebraic expressions
explain more for me to understand better pls
Answer:
[tex]61\% = \frac{61}{1 00 } \:→fractional \: expression \\ 61\% = 0.61 \: → decimal \: expression[/tex]
find the product of (5t-3) and (3t +7) when t = 6
Answer:
675
General Formulas and Concepts:
Pre-Algebra
Order of Operations: BPEMDAS
Brackets Parenthesis Exponents Multiplication Division Addition Subtraction Left to RightStep-by-step explanation:
Step 1: Define
(5t - 3) · (3t + 7)
t = 6
Step 2: Evaluate
Substitute in t: (5(6) - 3) · (3(6) + 7)(Parenthesis) Multiply: (30 - 3) · (18 + 7)(Parenthesis) Subtract: 27 · (18 + 7)(Parenthesis) Add: 27 · 25Multiply: 675Answer:
(5t -3)(3t+7) (im multiplying them together, if that's not what the questions asking lmk. but anyway, put them next to eachother and then plug in 6 for t)
(5(6) -3)(3(6)+7) (multiply where possible)
(30 -3)(18+7) (use the distributive property/foil to multiply the two)
540 +210 -54 -21 (add the positive numbers and subtract the negative )
750 - 75 (subtract)
675 (the answer)
Step-by-step explanation:
I hope this helps :)
Rewrite in simplest terms: -0.2t - 5 (-8t + 5)
Answer: 40.2t - 25
Step-by-step explanation:
-0.2t - 5 (-8t + 5)
-0.2t + 40t -25
39.8t - 25
pretty please help.
What is the area of the of the object above ?
A. 98 sq cm
B. 54 sq cm
C. 104 sq cm
D. 90 sq cm
Answer:
the answer is d
Step-by-step explanation:
basically dived that shape to 2 peices.
the big rectangle: 12 x 7 = 84
the small rectangle: 2 x 3 = 6
then add these 2 areas together to get the area of the object: 84 + 6 = 90
therfore, teh area of the object is 90 sq cm
mark brainliest plz :P
1. (04.01 LC)
Which unit rate is equivalent to 14 miles per gallon? (1 point)
2 gallons/32 miles
32 miles/2 gallons
3 gallons/42 miles
42 miles/3 gallons
Answer:
42 miles/3 gallons
Step-by-step explanation: Multiplying 14 by 3 and 1 by 3 will give you 42/3, which keeps the unit ratio.
Answer:
42 miles/3 gallons
Step-by-step explanation:
PLEASE ANSWER ASAP FOR BRAINLEST!!!!!!!!!!!!!!!!!!!
Answer: C isn't correct.
Step-by-step explanation:
C is NOT correct
The equation that represents the situation is y = 50x not x = 50y
Hope I helped! :3
what is an absolute value
Answer:
the magnitude of a real number without regard to its sign
Step-by-step explanation:
An example would be :
-16 =[16]
The ratio of boys to girls in a class is 5:7.
There are 36 students in the class.
How many more
girls than boys are there?
Answer:
6 more girls than boys
Step-by-step explanation:
7+5=12
36 divided by 12 = 3
3x7=21
3x5=15
Can you help me with this question?
The amount people who pay for cell phone service varies quite a bit, but the mean
monthly fee is $55 and the standard deviation is $22. The distribution is not Normal.
Many people pay about $30 for plans with 2GB data access and about $60 for 5GB
of data access, but some pay much more for unlimited data access. A sample survey
is designed to ask a simple random sample of 1,000 cell phone users how much they
pay. Let x be the mean amount paid.
Part A: What are the mean and standard deviation of the sample distribution of X?
Show your work and justify your reasoning. (4 points)
Part B: What is the shape of the sampling distribution of x? Justify your answer. (2
points)
Part C: What is the probability that the average cell phone service paid by the
sample of cell phone users will exceed $56? Show your work. (4 points) (10 points)
INTL
Answer:
a) The mean is $55 and the standard deviation is $0.6957
b) The shape of the sampling distribution of x is approximately normal.
c) 0.0749 = 7.49% probability that the average cell phone service paid by the sample of cell phone users will exceed $56.
Step-by-step explanation:
Normal probability distribution
When the distribution is normal, we use the z-score formula.
In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the zscore of a measure X is given by:
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
Central Limit Theorem
The Central Limit Theorem estabilishes that, for a normally distributed random variable X, with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean [tex]\mu[/tex] and standard deviation [tex]s = \frac{\sigma}{\sqrt{n}}[/tex].
For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.
For a proportion p in a sample of size n, the sampling distribution of the sample proportion will be approximately normal with mean [tex]\mu = p[/tex] and standard deviation [tex]s = \sqrt{\frac{p(1-p)}{n}}[/tex]
In this question:
Mean of the distribution: 55
Standard deviation of the distribution: 22
Sample of 1000.
This means that:
[tex]\mu = 55, \sigma = 22, n = 1000[/tex]
Part A: What are the mean and standard deviation of the sample distribution of X?
By the Central Limit Theorem, the mean is 55 and the standard deviation is [tex]s = \frac{22}{\sqrt{1000}} = 0.6957[/tex].
Part B: What is the shape of the sampling distribution of x?
By the Central Limit Theorem, the shape of the sampling distribution of x is approximately normal.
Part C: What is the probability that the average cell phone service paid by the sample of cell phone users will exceed $56?
This is 1 subtracted by the pvalue of Z when [tex]X = 56[/tex]. So:
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
By the Central Limit Theorem
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]Z = \frac{56 - 55}{0.6957}[/tex]
[tex]Z = 1.44[/tex]
[tex]Z = 1.44[/tex] has a pvalue of 0.9251
1 - 0.9251 = 0.0749
0.0749 = 7.49% probability that the average cell phone service paid by the sample of cell phone users will exceed $56.
as an estimation we are told £3 is €4. Convert €52 to pounds.
Answer:
its £39
Step-by-step explanation:
Rewrite each of the following expressions so that the number inside the radical is as small as possible. For example, rewrite √18 as 3√2.
√50=
√28=
√252=
Answer:
1) [tex]\mathbf{\sqrt{50}= 5\sqrt{2} }[/tex]
2) [tex]\mathbf{\sqrt{28}= 2\sqrt{7} }[/tex]
3) [tex]\mathbf{\sqrt{252}= 6\sqrt{7} }[/tex]
Step-by-step explanation:
We need to simplify the radicals:
1) [tex]\sqrt{50}[/tex]
First we find prime factors of 50
50 = 2 x 5 x 5
Now,
[tex]\sqrt{50}\\=\sqrt{2\times 5\times 5}\\=\sqrt{2\times 5^2}\\ =\sqrt{2} \sqrt{5^2}\\=5\sqrt{2}[/tex]
So, [tex]\mathbf{\sqrt{50}= 5\sqrt{2} }[/tex]
2) [tex]\sqrt{28}[/tex]
First we find prime factors of 28
28 = 2 x 2 x 7
Now,
[tex]\sqrt{28}\\=\sqrt{2\times 2\times 7}\\=\sqrt{2^2\times 7}\\ =\sqrt{2^2} \sqrt{7}\\=2\sqrt{7}[/tex]
So, [tex]\mathbf{\sqrt{28}= 2\sqrt{7} }[/tex]
3) [tex]\sqrt{252}[/tex]
First we find prime factors of 252
50 = 2 x 2 x 3 x 3 x 7
Now,
[tex]\sqrt{252}\\=\sqrt{2\times 2\times 3\times 3 \times7}\\=\sqrt{2^2\times 3^2 \times7}\\ =\sqrt{2^2} \sqrt{3^2}\sqrt{7} \\=2\times 3\sqrt{7}\\=6\sqrt{7}[/tex]
So, [tex]\mathbf{\sqrt{252}= 6\sqrt{7} }[/tex]
All of the following expressions are equivalent, except ______.
x - 7
7 + (-x)
-x + 7
7 - x
Answer:
x - 7
Step-by-step explanation:
Let's let x = 4 and see which one would be different
x - 7 = 4 - 7 = -3
7 + (-x) = 7 + -4 = 3
-x + 7 = -4 + 7 = 3
7 - x = 7 - 4 =3
As you can see, the top answer would be negative while all the rest are positive. This is because, in that case, the negative sign was attached to the 7 instead of the x.
Answer:
x - 7
Step-by-step explanation:
Using powers of ten, which would be the best choice for the first number to subtract in the division problem 4860 divided by 15?
a music store sells a used guitar for $120. This is $25 more than 1/2 the cost of a new guitar of the same brand. what is the cost of a new guitar?
Answer:
$190.
Step-by-step explanation:
We can write the equation 120=25+1/2n where n is the cost of a new guitar. First, we subtract 25 from both sides to get 95=1/2n. Then, we multiply both sides by 2 to get 190=n. Therefore, the cost of a new guitar is $190.
After dinner 2/3 of a pan of lasagna is left. The whole pan of lasagna was originally cut into pieces 1/6 of the pan. Which equation represents the number of pieces of lasagna that are left after dinner
Answer:
There are 4 pieces of lasagna left
Help please! Help me please! I don’t understand! I’ll give you brainly!
Answer:
Its a monomial of degree 0
Step-by-step explanation:
pls mark brainliest
Answer:
The expression represents a polynomial. The polynomial is a monomial and has a degree of 1
Step-by-step explanation:
First lets look at the definitions of these words:
Monomial means that there is only one term in the equation
Binomial means there is 2 terms
Trinomial means there is 3
and polynomial means 4 or more
The equation would be a monomial because it only has 1 term in it.
Now lets look at the degree.
To find the degree lets take a look at how to make radicals into exponents
So you have [tex]-\sqrt{2}[/tex]
You know that when you square root something, the degree of the radical sign is 2.
That is not the degree its asking for though. Its asking for the degree of 2
In exponential form the equation is [tex]-2^{\frac{1}{2} }[/tex]
Reason for this being that the numerator is the exponent for whatever is inside the radical sign while the denominator is for the square root symbol.
So if you have [tex]-2^{\frac{3}{4} }[/tex] for example, the radical form is [tex]-\sqrt[4]{2^{3} }[/tex]
So the numerator would be the degree.
If there is no degree for the function, as in you don't see an exponent then that means the exponent = 1
If you need further assistance don't be afraid to reach out. I hope this helps!
Please help I’ll mark you as brainliest if correct!!
Answer:
2 handshakes
Step-by-step explanation:
10 divided by 5 is 2
solve. 7/20n = 8/5. enter a fraction or a whole number
Answer:
7/32
Step-by-step explanation:
[tex]\frac{7}{20n}=\frac{8}{5}[/tex]
we can multiply the elements on the diagonal so
20n*8=7*5
160n=35
we divide the relation by 160
n=35/160=7/32
Advance Algebra Logarithm Task
Assume your friend, Natalie, has $10,000 to invest. Complete the following chart to show how
much she would earn if her money was invested in each of the specified accounts for 10 years.
Frequency of Annual interest Formula with values Amount after 10
compounding
substituted in
years
Quarterly 3.65%
Monthly
3.65%
Continuously
3.6%
rate
Which account would you suggest for Natalie? Continuously
9514 1404 393
Answer:
3.65% monthly
Step-by-step explanation:
The same amount is invested for the same period in all accounts, so we only need to determine the effective annual rate in order to compare the accounts.
For compounding annual rate r n times per year, the effective annual rate is ...
(1 +r/n)^n -1
For the same rate r, larger values of n cause effective rate to be higher. As a consequence, we know that 3.65% compounded quarterly will not have as great a yield as 3.65% compounded monthly. The effective rate for the monthly compounding is ...
(1 +0.0365/12)^12 -1 = 3.712%
The effective rate for continuous compounding is ...
e^r -1
For a continuously compounded rate of 3.6%, the effective annual rate is ...
e^0.036 -1 = 3.666%
This tells us the best yield is in the account bearing 3.65% compounded monthly.
_____
If i is the effective annual rate of interest as computed by the methods above, then the 10-year account balance will be ...
10000×(1 +i)^10
This is the formula used in the spreadsheet to calculate the balances shown.
An amusement park charges $5 for admission and $.80 for each ride. You go to the park with $13. Which inequality represents this situation
Answer:
Answer Placeholder (I'm going to solve it and answer when I'm done)
Step-by-step explanation:
Please help, will read you with Brainliest. Please check ALL that apply.
Answer:correct answers are:
A.m<JPX=90°
B.XY & JK form right angles
E. JP=KP
F.XY⊥JK
Step-by-step explanation:
hope this helps
Find the circumference and area of each circle. Use your calculator's value of t. Round your answer to the nearest tenth. Circumference 9m
Answer: Duno
Step-by-step explanation:
Identify all the corresponding angles below. Select all that apply.
Answer:
A,B,D,E
Step-by-step explanation:
hope u get to right
math geeks please help :(
9514 1404 393
Answer:
7th grade: 16
5th grade: 13
7th grade median is higher by 3 points
Step-by-step explanation:
There are 21 dots in each plot, so the median score will be the score associated with the 11th dot, counting from either end.
In the 7th-grade data, that dot is in the "16" column. The 7th grade median is 16.
In the 5th-grade data, that dot is in the "13" column. The 5th grade median is 13.
__
The 7th grade median is higher by 3 points.
_____
Additional comment
Your options for filling in the relationship of the scores are not shown. You may have to interpret the result according to the options available.
What is the GCF of the polynomial given below?
60ax - 40ay + 50az
Answer: 10a, all of the numbers can be divided by 10a
10a (6x − 4y + 5z) = 60ax - 40ay + 50az
Which ordered pair, when graphed, would not show a function?
(miles per gallon, gallons in tank)
(length of shadows/time of day)
(temperature in F, temperature in C)
O (number of employees, number of hours worked)
Answer: its the last answer I got it right
The figure below is made up of two rectangular prisms.
3 m
7 m
10 m
4 m 1 m
Find the volume of the entire figure by adding the volumes of the separate figures.
Volume = 120 +
cubic meters
Answer:
Total Volume = 190 m³Step-by-step explanation:
Volume of the entire figure = L (Area 1 + Area 2)
where L = 10 m
Area 1 (blue prism) = 4 x 3 = 12 m²
Area 2 (brown prism = 1 x 7 = 7 m²
plugin values into the formula:
Volume of the entire figure = L (Area 1 + Area 2)
= 10 (12 + 7)
= 120 m³ + 70 m³
= 190 m³