How to do chi-squared question on AP Bio?

Test Preparation AP Test Preparation
1

<p>Grid in question
I know the formula and sort of understand it, but can anyone explain it to me if I'm wrong?</p>

<p>So first basically the expected value is the mean of all the observed values.</p>

<p>Then I subtract each and square each number
And then that divided by the expected.</p>

<p>And finally add them together.</p>

2

<p>Nvm I got it right on my practice test in school.</p>