Finding margin or error

[Tarabara100]

Find the margin of error for the 95% confidence interval.

1) N=169 X=107

2. N=230 X=90

If someone could help me figure out how to answer these by 6 that would be great thanks!

 

[tkhunny]

Definitions, please.

What is "N"?
What is "X"

Is that really the notation you intend?

What does your text say about these issues?

Have you ever seen this?
\(\displaystyle N = \frac{z^{2}\cdot s^{2}}{d^2}\)

Can you solve for "d"?