Modeling Ratios

Question

Adam's sister is 4 years younger than Adam. The current ratio of Adam's age to his sister's age is 5:3. What will the ratio of Adam's age to his sister's age be in 5 years?

Answer 1

First, let's find Adam's age and his sister's age today.

Let A = Adam's age today

S = his sister's age today

Given: S = A - 4

A/S = 5/3

Solving we find S = 6 and A = 10

So in 5 years, Adam will be 15 and his sister will be 11

Then A/S = 15/11