Expressions and Equations: Solving Real-World Problems with Equations (CCSS.6.EE.7) Practice Test

Liam had some marbles. After getting 7 more, he has 12. Which value makes the equation $x + 7 = 12$ true?

Three equal boxes weigh 15 pounds in total. Let $x$ be the weight of one box. What is the solution for $x$ in $3x = 15$?