### Home > MC1 > Chapter 1 > Lesson 1.1.2 > Problem 1-15

1-15.

Maria's brother came back with another problem. He said, *"If you multiply my number by and add you get ." *

What number was he thinking of?

Having trouble? Go back and look at the 1-14, because that problem is very similar to this one.

Remember to pick a reasonable number and use it to do the steps that Maria's brother describes.**Explain**how you figured out your answers to Maria's and her brother's number puzzles.Did you guess and then check whether your guess worked?

Did you work backwards?