I have a sixth grade ratio problem, can anyone help me?

Question

My son forgot his book at school, and i can't find any examples online. The problem is as follows: holly said that the ratio of her allowance to Felicia's allowance is the same as Felecia's allowance is to manny's allowance. If holly's allowance is $16 and Manny's allowance is $25, then how much is Felicia's allowance. I don't want to give my son the answer, but i need to understand it to explain it to him

Answer 1

Ratio of Holly's allowance to Felecia's is 16 to X, or 16/X

Felecia's to Manny's is X to 25, or X/25.

Therefore 16/X = X/25, and you can solve for X by doing the following:

X squared = (16)(25)

X squared = 400

square root of 400 = 20

$20 is Felecia's allowance