When will we be the same age?

Algebra Level 1

My brother is 4 times my age right now, and he will be 3 times my age in 3 years.

In how many more years after that will he be 2 times my age?

11 9 7 5

1 solution

Blan Morrison
Oct 8, 2018

Let $a$ and $b$ be you and your brother, respectively. We start with the system of equations $b=4a$ $b+3=3a+9$ Using substitution $4a=3a+6$ $\implies a=6$ $\implies b=4(6)=24$ Let $y$ be the amount of years such that $b+y=2(a+y)$ : $24+y=12+2y$ $\implies 12=y$ Therefore, the amount of years after those 3 years is $y-3=12-3=\boxed{9}$ .

When will we be the same age?

1 solution

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