Answer:
The minimum sample size needed is 39.
Step-by-step explanation:
We have that to find our [tex]\alpha[/tex] level, that is the subtraction of 1 by the confidence interval divided by 2. So:
[tex]\alpha = \frac{1 - 0.99}{2} = 0.005[/tex]
Now, we have to find z in the Ztable as such z has a pvalue of [tex]1 - \alpha[/tex].
That is z with a pvalue of [tex]1 - 0.005 = 0.995[/tex], so Z = 2.575.
Now, find the margin of error M as such
[tex]M = z\frac{\sigma}{\sqrt{n}}[/tex]
In which [tex]\sigma[/tex] is the standard deviation of the population and n is the size of the sample.
Assuming that the standard deviation of the number of hours is 120 hour
This means that [tex]\sigma = 120[/tex]
The minimum sample size needed in order to construct a 99% confidence interval for the mean number of hours of flight time of all such pilots, to within 50 hours, is about?
The minimum sample size needed is n.
n is found when [tex]M = 50[/tex]
So
[tex]M = z\frac{\sigma}{\sqrt{n}}[/tex]
[tex]50 = 2.575\frac{120}{\sqrt{n}}[/tex]
[tex]50\sqrt{n} = 2.575*120[/tex]
[tex]\sqrt{n} = \frac{2.575*120}{50}[/tex]
[tex](\sqrt{n})^2 = (\frac{2.575*120}{50})^2[/tex]
[tex]n = 38.19[/tex]
Rounding up
The minimum sample size needed is 39.
5th grade math. correct answer will be marked brainliest
Answer:
sorry but the picture if you put one on here isn't showing up maybe Repost and I could answer
What is the factored form of this expression? 27n3+125n3
Answer:
27n³+125n³ = 152n³
5.337n)(5.337n)(5.337n)
Answer:
Step-by-step explanation: use math-way a chegg service
100% of 80 is what number?
Select one:
160
80
8
100
Answer:
80
explanation:
100% means that its the whole of something so all of the said number
Answer:
In converting to percentage we multiply by 100%
100% of 80 =
80/100 x 100%
0.8 x 100 = 80
NB the 100% of any number is the number itself
Pedro is building a playground in the shape of a right triangle. The base of the triangle is 18 yards. The height of the right triangle is 2 1/3 yards. Find the area of the triangular playground.
Answer:
area of right triangle = ab/2
base = 18yards
height = 2 1/3 = 7/3yards
area = (18 * 7/3) /2 = 42 /2 = 21[tex]yards^{2}[/tex]
hope this answer helps you.....
f(x)=-2x² + 3x-6, find f (3)
Answer:
f(3) = -15
General Formulas and Concepts:
Pre-Algebra
Order of Operations: BPEMDAS
Brackets Parenthesis Exponents Multiplication Division Addition Subtraction Left to RightAlgebra I
FunctionsFunction NotationStep-by-step explanation:
Step 1: Define
f(x) = -2x² + 3x - 6
f(3) is x = 3 for the function f(x)
Step 2: Evaluate
Substitute in x [Function]: f(3) = -2(3)² + 3(3) - 6Exponents: f(3) = -2(9) + 3(3) - 6Multiply: f(3) = -18 + 9 - 6Add: f(3) = -9 - 6Subtract: f(3) = -15Answer:
f(3) = -15
General Formulas and Concepts:
Pre-Algebra
Order of Operations: BPEMDAS
Brackets
Parenthesis
Exponents
Multiplication
Division
Addition
Subtraction
Left to Right
Algebra I
Functions
Function Notation
Step-by-step explanation:
Step 1: Define
f(x) = -2x² + 3x - 6
f(3) is x = 3 for the function f(x)
Step 2: Evaluate
Substitute in x [Function]: f(3) = -2(3)² + 3(3) - 6
Exponents: f(3) = -2(9) + 3(3) - 6
Multiply: f(3) = -18 + 9 - 6
Add: f(3) = -9 - 6
Subtract: f(3) = -15
I need help please.
 Consider the line segment LP with endpoint at L (-3, -5) and P (9, 7) and midpoint M.
What is the x—coordinate of N, the point that partitions segment MP in a 1 : 1 ratio?
A. 4
B. -4
C. -6
D. 6
Answer:
D. 6
Step-by-step explanation:
Finding M:
M is the midpoint of L and P, which is given by the mean coordinates of L and P.
x for L is -3, and for P is 9. So
(-3 + 9)/2 = 6/2 = 3
Finding N:
N is the midpoint between M and P, that is, the mean between the coordinates of M and P. So
(3 + 9)/2 = 12/2 = 6
The correct answer is given by option D.
Take home pay is equal to
Answer:
gross income - ( required deductions + optional deductions )
-2 4/5 divided by -7
Answer:
2/5 or 0.4
Step-by-step explanation:
convert -14/5 / (-7)
divide 14/5 / 7 ( two negatives equal a positive)
equals 2/5 or 0.4 in decimal
Plzzzzzz helpppp me
Answer:
15
Step-by-step explanation:
Just substitute x in the equation
so x=3
so
3^2=9, 5x3=15, -9
equals 15
VERY EASY, WILL GIVE 50 POINTS FOR CORRECT ANSWER ASAP AND WILL GIVE BRAINLIEST.
Answer:
(3, -2)
Step-by-step explanation:
Wally counted 200 pennies from his piggy bank. He kept 80% of them. How many pennies did Wally keep?
Select one:
160
60
80
120
What value of x makes the following equation true x + 10 = 18
Step-by-step explanation:
The value should be
X=18-10= 8
X=8 Answer
A car and a truck left Washington, DC traveling in opposite directions. The car traveled 19 miles per hour faster than the truck, and at the end of 8 hours they were 1048 miles apart. What was the average speed of each vehicle?
100 POINTS
Answer:
Step-by-step explanation:xmccc
Can someone please give me this answer
Answer:
42°
Step-by-step explanation:
According to Exterior Angle Theorem,
an exterior angle of a ∆ is equal to the sum of the opposite interior angles.
So,
h+96°=138°
h=138°-96°
h=42°
Show your work
2) Is(-3,-7) a solution to
4x – 8y < 24
Show your work
Answer: false, 44 is not less than 24
Step-by-step explanation:
Substitute-3 for x and -7 for y.
4(-3)-8(-7)<24
-12+56<24
44<24
Mr. Ledford is concerned about the amount of sleep the students in his district are getting. He selects a random sample of 14 seniors in his district and asks them how many hours of sleep they get on a typical school night. He then uses school records to determine the most recent grade-point average (GPA) for each student. His regression output along with a residual plot and a histogram of the residuals are given below.
Sleep (hrs) 9 8.5 9 7 7.56 7 5.5 6 8.5 6.5 8
GPA 3.8 3.3 3.5 3.6 3.4 3.3 3.2 3.2 3.2 3.4 3.6 3.1 3.4 3.7
Required:
Do these data provide convincing evidence of a linear relationship between the hours of sleep students typically get and their academic performance, as measured by their GPA?
Answer:
Hence, the data provides convincing evidence that a linear relationship exists between hours of sleep observed and academic performance as measured by GPA.
Step-by-step explanation:
Given the data:
Sleep (hrs) 9 8.5 9 7 7.56 7 5.5 6 8.5 6.5 8
GPA 3.8 3.3 3.5 3.6 3.4 3.3 3.2 3.2 3.2 3.4 3.6 3.1 3.4 3.7
The scatter plot shows a positive linear trend. With the correlation Coefficient depicting a R value of 0.56. The residual plot also depicts a a randomly scattered values of the residual values. Similarly, a plot of the normal values of residuals
The data provided has a linear correlation between the hours of sleep observed and academic performance as measured by GPA.
What is correlation?It is defined as the relation between two variables which is a quantitative type and gives an idea about the direction of these two variables.
We have given data of the 14 seniors shown in the table.
To solve this question we will calculate the correlation coefficient 'r'
The formula for correlation coefficient :
[tex]\rm r =\frac{n\sum xy-\sum x \sum y}{\sqrt{[n\sum x^2-(\sum x)^2]}[n\sum y^2-(\sum y)^2]} }[/tex]
From the table the value of n = 14
[tex]\rm \sum x = 104.5[/tex] , [tex]\rm \sum y =47.7[/tex] , [tex]\rm \sum xy =357.8[/tex] , [tex]\rm \sum x^2 =797.25[/tex] , [tex]\rm \sum y^2 =163.09[/tex]
Put all the values in the above formula we get:
[tex]\rm r =\frac{14\times357.8-104.5 \times47.7}{\sqrt{[14\times 797.25-104.5^2][14\times163.09-47.7^2]} }[/tex]
[tex]\rm r = \frac{5009.2-4984.65}{\sqrt{(241.25)(7.97)} }[/tex]
[tex]\rm r = \frac{24.55}{43.849}[/tex]
r = 0.559 ≈ 0.56
The value of the correlation coefficient is 0.56 which is between the values 0.5 to 0.7 shows that the variables are moderately correlated.
Thus, the data provided has a linear correlation between the hours of sleep observed and academic performance as measured by GPA.
Learn more about the correlation here:
brainly.com/question/11705632
You need two bottles of fertilizer to treat the flower garden that has a perimeter of 42 feet. How many bottles do you need to treat a similar garden with a perimeter of 105 feet?
Answer:
5
Step-by-step explanation:
y = -x + 2 –6x + 2y = 8
Answer:
rewrite the whole expression;
X+Y =2
-6x + 2y = 8
divide the 2nd expression by 2 on both sides we get
-3x + y = 4
substract the 1st expression from the newly found 2nd expression
-3x-x + y-y = 8-2
-4x = 6; x= 3/2
y = 2-(3/2) = 1/2
x= 3/2 , y= 1/2
. The figure below shows a circular
driveway. What is the area of the
driveway?
Answer:
C
Step-by-step explanation:
A= πr squared
D=r*2
r=24
π=3.14
A= π(24 * 24) = 576
A= π576
A=10808.64
A=10808.6
Choose the sets of equivalent expressions (select all that apply)
A. 4x and 5 + x
B. 2b + b and 3b
C. 3x and 3 + x
D. a ÷ 1/3 and 1/3 a
E. a ÷ 1/3 and a × 3
F. 1a and a
9514 1404 393
Answer:
B, E, F
Step-by-step explanation:
A. 4x and 5 + x
B. 2b + b and 3b
C. 3x and 3 + x
D. a ÷ 1/3 and 1/3 a
E. a ÷ 1/3 and a × 3
F. 1a and a
_____
Comment on the above
ax is multiplication of x by 'a'. a+x is addition. They are different operations.
x/(1/3) is not the same as x(1/3). Multiplication and division are different operations.
Please help me out here.............
Need answer please !!
Need Help ASAP : Math Question : Professional football field is 160 feet wide. What's the width of the field in yards?
Answer:
53.3333
Step-by-step explanation:
I took 160 feet and converted it to yards
This solid was created by joining two right rectangular prisms.
7 cm
9 cm
5 cm
4
4 / 3cm
12 cm
Enter the volume of the solid in cubic centimeters.
Answer: 648
Step-by-step explanation:
if you add an exclamation I will give you a Brain list
A male animal can weigh up to 6,000 pounds.
How many tons is 6,000 pounds?
6,000 pounds is equivalent to what
tons.
Answer:
it would be 3 tons if I'm correct
Answer: 3 tons
Step-by-step explanation:
1 ton is equal to 2,000 pounds.
Divide 6,000 from 2,000 to find how many tons the animal weighs.
6,000/2,000=3.
Hope this helps!
Find the mean absolute deviation of the setback of data. 9, 12, 3, 5, 8
Answer:
3.5
Step-by-step explanation:
Inequality question PLEASE HELP
Answer:
40x4x<60
x<5
Step-by-step explanation:
40x4x<60
4x<60-40
4x<20
x<20÷4
x<5
A high-school administrator who is concerned about the amount of sleep the students in his district are getting selects a random sample of 14 seniors in his district and asks them how many hours of sleep they get on a typical school night. He then uses school records to determine the most recent grade-point average (GPA) for each student. Here is the regression output. Assume the conditions for inference are met. 1.
Predictor Coef SE Coef T P
Constant 2.6476 0.3281 8.07 0.000
Sleep 0.10176 0.04347 **** *****
S = 0.1804
R-Sq = 31.3%
R-Sq(adj) = 25.6%
Required:
Predict the GPA for a senior in this district who gets 8 hours of sleep on a typical school night.
Answer:
3.46
Step-by-step explanation:
Given the regression output :
Predictor Coef ___SE __ Coef __ T ___ P
Constant 2.6476_0.3281_ 8.07 0.000
Sleep 0.10176 0.04347 **** *****
S = 0.1804
R-Sq = 31.3%
R-Sq(adj) = 25.6%
The regression equation which models the relationship between hours of sleep a student gets and his GPA can be obtained from the regression output :
The GPA is the dependent, y variable
Hours of sleep is the independent, x variable
y = 0.10176x + 2.6476
Hence, the GPA of a student who gets 8 hours of sleep on a typical school can be computed thus ;
Hours of sleep, x = 8
y = 0.10176(8) + 2.6476
y = 0.81408 + 2.6476
y = 3.46168
Thus, predicted GPA = 3.46
PLEASE ANSWER FOR BRAINLEST!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!1
Jeff wants to form a garden that is in the shape of a triangle. He has two lengths of fence that are 19 feet long and 12 feet long. He says he will be able to form a triangular garden with a third length of fence that is 8 feet long. Is Jeff correct or incorrect in his reasoning? Explain.
Answer: Jeff is correct.
Step-by-step explanation:
The sum of the two sides of the triangle must greater than the longest side, which in this case, the longest side is 19 feet.
8 + 12 ? 19
20 > 19
Therefore, Jeff is correct.