  ### Home > ACC6 > Chapter 1 Unit 10 > Lesson CC2: 1.1.2 > Problem1-15

1-15.

Maria was playing a game with her brother. She said, “I’m thinking of a number. When you multiply my number by six and add seven, you get twenty-five. What is my number?”

1. Find Maria’s number.

How big do you expect her number to be? Can you think of a reasonable number to try?

Pick a reasonable number and try Maria's steps. Let's try $2$. If Maria multiplies this number ($2$) by $6$, she would get $12$. Then, adding $7$, she would get $19$.

Can you think of a number that might work better? Try it!

Since $19$ is smaller than $25$, let's choose a bigger number. Let's try $3$. If Maria multiplies $3$ by $6$, she would get $18$. Adding $7$, she would get $25$. Since Maria gets $25$ by using this number, $3$ is the number she described.

We now know that Maria's number is $3$.

2. Explain how you figured out your answer to Maria’s number puzzle.

Can you describe with words the steps that you took to find Maria's number?