Question

Carrie is twice as old as Samantha. Together their ages total 21.Choose the equation and solve.

Answer 1

Let's define the variables:

- Let \( C \) be Carrie's age.
- Let \( S \) be Samantha's age.

From the problem, we have the following two equations:

1. \( C = 2S \) (Carrie is twice as old as Samantha)
2. \( C + S = 21 \) (Together their ages total 21)

Now we can substitute the first equation into the second equation:

Substituting \( C \) in the second equation gives us:

\[
2S + S = 21
\]

This simplifies to:

\[
3S = 21
\]

Now, divide both sides by 3 to find \( S \):

\[
S = 7
\]

Now that we have Samantha's age, we can find Carrie's age using the first equation:

\[
C = 2S = 2(7) = 14
\]

So, Carrie's age is 14, and Samantha's age is 7.

To summarize:

- **Carrie's age**: 14
- **Samantha's age**: 7