# Sample size

Not what you're looking for? Search our solutions OR ask your own Custom question.

A poll of 1400 randomly selected students in grades 6 through 8 was conducted and found that 30% enjoy playing sports. Would confidence in the results increase if the sample size were 3200 instead of 1400? Why or why not?

Â© BrainMass Inc. brainmass.com March 4, 2021, 6:17 pm ad1c9bdddfhttps://brainmass.com/statistics/confidence-interval/sample-size-38633

#### Solution Preview

sample proportion= 30%

We have to estimate the population proportion from the sample proportion.

This will lie in a range called the confidence limits.

We have to calculate confidence interval for sample sizes

n= 1400

and

n= 3200

at the same level of significance alpha (a) , say = 5%

Confidence limits when n= 1400

p= 30.00%

q=1-p= 70.00%

n=sample size= 1400

sp=standard error of proportion=square root of (pq/n)= 1.23% =square root of ( ...

#### Solution Summary

The solution calculates confidence intervals for different sample sizes.

$2.49