Question

type the answer in the box, using whole numbers.

q. the sum of the ages of bob and cathy is 84 years. in 3 years, bob will be twice as old as cathy. how old is cathy now?
(hint: if \\(b\\) represents bobs age now, his age in 3 years will be \\(b + 3\\).)

Explanation:

Define variables and write the first equation

Using the Algebraic Expressions knowledge point

$$
LATEXBLOCK0
$$

Formulate the second equation

Using the Systems of Equations knowledge point

$$
LATEXBLOCK1
$$

Solve for Cathy's age using substitution

Using the Substitution Method knowledge point

$$
LATEXBLOCK2
$$

Answer:

The sum of the ages of Bob and Cathy is 84 years. In 3 years, Bob will be twice as old as Cathy. How old is Cathy now? <blank>27</blank>