1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
miss Akunina [59]
3 years ago
15

A statistics student would like to estimate the average age of students at her college. she would like to be 85% confident that

her estimate includes the actual college population mean. she did a smaller preliminary survey and found that a reasonable estimate of the population standard deviation was 4 1/2 years. how many people must she survey if she wants to be within 1/2 year of the true population mean? please round off your answer to the nearest integrer.

Mathematics
1 answer:
Anna11 [10]3 years ago
7 0

A statistics student would like to estimate the average age of students at her college. she would like to be 85% confident that her estimate includes the actual college population mean

It means confidence level is 0.85.

After taking survey the estimate of population standard deviation is found as 4.5 years. The given margin of error is 0.5 years

The sample size is obtained using formula

n= (\frac{z_{\alpha/2} std}{ME} )^{2}

Where std = standard deviation

alpha = 1 -c = 1-0.85 = 0.15

z(α/2) = z(0.15/2) = z(0.075)

It is the critical value of z such that area above z and below -z is 0.075

Use z score table to find the probability exactly or very close to 0.075 and note the corresponding z score value.

In z score table there is no accurate 0.075 probability value. The close value is 0.0749 which corresponds to z score -1.44

For calculation we take positive z score value.

So we get z(α/2) =1.44

Using all the given values into formula

n = [(1.44 * 4.5) / 0.5]^2

n = 167.96

Rounding it to nearest integer we get n=168

The number of people need to surveyed is n=168

You might be interested in
Least to greatest 3/6 3/4 2/8
-Dominant- [34]

Answer:

2/8 3/6 3/4. That is least to greatest

5 0
3 years ago
Read 2 more answers
(05.08A)Triangle ABC is transformed to similar triangle A′B′C′ below:
Romashka-Z-Leto [24]

Answer:

1st option is correct i.e., 1 over 2

Step-by-step explanation:

Given that Triangle ABC transformed to Triangle A'B'C'.

Coordinated of Triangle ABC are A(2,6) , B(2,4) and C(4,4)

Coordinated of Triangle A'B'C' are A'(1,3), B'(1,2) and C'(2,2)

Scale factor of Dilation is the no. of times coordinates of vertices of a figure increase or decrease.i.e.,

if A(a,b) ⇒ A'(c,d)

where, a.k=c & b.k=d then k is scale factor of dilation.

Value of k is same for all vertices.

For coordinates of A & A' ,we have 2.k=1\implies k=\frac{1}{2} \:\: and \:\: 6.k=3\implies k=\frac{1}{2}

For coordinates of B & B' ,we have 2.k=1\implies k=\frac{1}{2} \:\: and \:\: 4.k=2\implies k=\frac{1}{2}

For coordinates of C & C' ,we have 4.k=2\implies k=\frac{1}{2} \:\: and \:\: 4.k=2\implies k=\frac{1}{2}

Therefore, the scale factor of dilation is \:\frac{1}{2}\:  since in all cases k=\frac{1}{2}

1st option is correct i.e., 1 over 2

3 0
3 years ago
In 2002, Tiger Woods won the masters tournament. His scores were -4, -3, -2, and -1. What was his final score?
puteri [66]

Answer:

-10

Step-by-step explanation:

-4 + -3 = -7

-7 + -2 = -9

-9 + -1 = -10

3 0
3 years ago
Linda bought a cube jewelry box. The volume of the jewelry box is 64 cubic inches. What is the edge length of Linda’s jewelry bo
yawa3891 [41]

Answer:

The edge length will be equal to 4 inches.

Step-by-step explanation:

The volume of a cube = s * s * s (in which s represent side of the cube)

V = s * s * s

V = s³

64 = s³

64 = 4³

So edge length of the cube will be 4 inches.

7 0
3 years ago
CAN SOMEONE HELP ME WITH THISSSS
Semmy [17]

Answer:

no i cannot

Step-by-step explanation:

4 0
2 years ago
Other questions:
  • An ice cream shop sold 48 vanilla milkshake in a day which is 40% of the total number of milkshake sold that day.What was the to
    5·1 answer
  • ​it's believed that as many as 2222​% of adults over 50 never graduated from high school. we wish to see if this percentage is t
    13·1 answer
  • Mathew’s mom asked him to go to the store for her. To get to the store he walked seven blocks. He caught the bus and rode 13 blo
    6·2 answers
  • What is 0.875 simplest form
    6·2 answers
  • Suppose that the probabilities of a customer purchasing​ 0, 1, or 2 books at a book store are 0.20.2​, 0.20.2​, and 0.60.6​, res
    15·1 answer
  • 2 2/3x+1/2x=95 what is the value of x
    15·1 answer
  • Someone please help me with this...
    10·2 answers
  • Can someone help with this question
    12·1 answer
  • 4 cm 3 cm 4 cm 4 cm 3 cm What is the perimeter of the hexagon? O A 19 cm B. 23 cm OC. 24 cm O D. 26 cm E. 27 cm​
    8·1 answer
  • We use the inverse of the multiplication of the constant to isolate the variable We do this using property of equality:
    6·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!