### Home > CCA > Chapter 7 > Lesson 7.1.4 > Problem7-49

7-49.

This problem is a checkpoint for solving problems by writing equations. It will be referred to as Checkpoint 7A.

For each problem, write one or two equations to represent the situation and then solve. Be sure to define your variable(s) and clearly answer the question.

1. The Lee’s have three children. The oldest is twice as old as the youngest. The middle child is five years older than the youngest. If the sum of the ages is $57$, how old is each child?

2. In Katy’s garden there are $105$ ladybugs. They are increasing at two ladybugs per month. There are currently $175$ aphids and the number of aphids is decreasing at three aphids per month. When will the number of ladybugs and aphids in Katy’s garden be the same?

3. At the farmer’s market Laura bought three pounds of heirloom tomatoes. If the tomatoes are priced at $8$ for five pounds, what did Laura pay for her tomatoes?

4. Adult tickets for the school play cost $5$ and student tickets cost $3$. Thirty more student tickets were sold than adult tickets. If $1770$ was collected, how many of each type of ticket was sold?

Check your answers by referring to the Checkpoint 7A materials located at the back of your book.

Ideally, at this point you are comfortable working with these types of problems and can solve them correctly. If you feel that you need more confidence when solving these types of problems, then review the Checkpoint 7A materials and try the practice problems provided. From this point on, you will be expected to do problems like these correctly and with confidence.

Answers and extra practice are located in the back of your printed textbook or in the Reference Tab of your eBook.
If you have an eBook for CCA, login and then click the following link: Checkpoint 7A: Solving Problems by Writing Equations