Chapter 9.7, Problem 14OE

To determine

To express: the sum of age of Claire and Bob , 2 years ago in terms of b and c .

Answer to Problem 14OE

The expression is $b+c-4$ .

Explanation of Solution

Given information:

  $\begin{array}{l}b=\text{Bob's age}\\ c=\text{Claire's age}\end{array}$

Formula used:

Age problem.

Step1. The problem asks for the Bob’s age and Claire’s age now.

Step2. Let b = the Bob’s age now.

Let c = the Claire’s age now.

Step3. Use the facts of the problem to write two equations.

Step4. Solve the equations.

Calculation:

Consider ,

Let b = the Bob’s age now.

Let c = the Claire’s age now.

Age	Now	2 years ago
Bob	$b$	$b-2$
Claire	$c$	$c-2$

Therefore,

  $\begin{array}{l}=b-2+c-2\\ =b+c-4\end{array}$

Hence, the expression is $b+c-4$ .