Answer:
A sample of 1077 is required.
Step-by-step explanation:
In a sample with a number n of people surveyed with a probability of a success of 
, and a confidence level of 
, we have the following confidence interval of proportions.
In which
z is the zscore that has a pvalue of 
.
The margin of error is of:
42% of freshmen do not visit their counselors regularly.
This means that 
98% confidence level
So 
, z is the value of Z that has a pvalue of 
, so 
.
How large of a sample size is required?
A sample size of n is required, and n is found when M = 0.035. So
Rounding up:
A sample of 1077 is required.
Order the number:
15,34,71,75,75,78,78,78,82,90,90,94,100
Mode:78
Mean≈74.8
Median:78 is your final answer. Hope it help!
Answer:
≈ 15.08 units²
Step-by-step explanation:
The area (A) of the sector is calculated as
A = area of circle × fraction of circle
= πr² × 
( r is the radius )
= π × 6² ×
= 36π × = π × 
= 
≈ 15.08
Answer:
a)= 2
b) 6.324
c) P= 0.1217
Step-by-step explanation:
a) The mean of the sampling distribution of X`1- X`2 denoted by ux`-x` = u1-u2 is equal to the difference between population means i.e = 2 ( given in the question)
b) The standard deviation of the sampling distribution of X`1- X`2 ( standard error of X`1- X`2) denoted by σ_X`1- X`2 is given by
σ_X`1- X`2 = √σ²/n1 +σ²/n2
Var ( X`1- X`2) = Var X`1 + Var X`2 = σ²/n1 +σ²/n2
so
σ_X`1- X`2 =√20 +20 = 6.324
if the populations are normal the sampling distribution X`1- X`2 , regardless of sample sizes , will be normal with mean u1-u2 and variance σ²/n1 +σ²/n2.
Where as Z is normally distributed with mean zero and unit variance.
If we take X`1- X`2= 0 and u1-u2= 2 and standard deviation of the sampling distribution = 6.324 then
Z= 0-2/ 6.342= -0.31625
P(-0.31625<z<0)= 0.1217
The probability would be 0.1217
Answer:
Step-by-step explanation:
