Sara and Jake's Ages Problem

Sara is twice as old as Jake. In 4 years, the sum of their ages will be 42. What is Sara's current age?

Let $S$ represent Sara's current age and $J$ represent Jake's current age. Based on the information provided, we can establish the following equations:

$S = 2J$

$S + 4 + J + 4 = 42$

Simplifying the second equation gives $S + J + 8 = 42$, which can be rewritten as $S + J = 34$.