# Thread: Finding margin of error without population size? Urgent please.

1. ## Finding margin of error without population size? Urgent please.

I have this question to answer...

Suppose that you are interested in determining the average height of adult women living in New York City. You collect data on a random sample of 200 adult women living in NYC and find that they are 64 inches tall, on average. Assume the standard deviation of heights of adult women is 2.5 inches. What is the margin of error for confidence level of 95%?

What I am confused about it how am I to find the margin of error without knowing the population size?

Thanks!

2. ## Re: Finding margin of error without population size? Urgent please.

Originally Posted by PrincessKate
I have this question to answer...

Suppose that you are interested in determining the average height of adult women living in New York City. You collect data on a random sample of 200 adult women living in NYC and find that they are 64 inches tall, on average. Assume the standard deviation of heights of adult women is 2.5 inches. What is the margin of error for confidence level of 95%?

What I am confused about it how am I to find the margin of error without knowing the population size?

Thanks!
Because the population is in the millions you may treat it as infinite.

CB