Answer:
3s
Step-by-step explanation:
Given:
Jim is twice as old as his sister.
His sister's age is signified by the variable s.
∴ Jim's age is 2s.
You are trying to find the sum of both their ages, or add them together:
2s + s
Simplify. Combine like terms:
2s + s = 3s
3s is the expression you will use to find the sum of their ages.
