Lesson 3: Solving Equations Using Addition or Subtraction — Practice Questions

1. 1. A student spent $\$3$ on a snack and now has $\$14$ left. If $m$ represents the money he started with, write an equation to find his starting amount. ___

2. 2. A large pizza has 12 slices, which is 4 more slices than a small pizza. If $s$ represents the slices in a small pizza, which equation models this situation?

   • A. $s + 4 = 12$
   • B. $s - 4 = 12$
   • C. $12 - s = 4$
   • D. $s + 12 = 4$

3. 3. Leo gave 8 rocks from his collection to a friend. He now has 35 rocks left. If $r$ was his starting number of rocks, write an equation for this situation. ___

4. 4. A building is 60 feet tall. This is 18 feet taller than a nearby tree. If $h$ is the height of the tree, write an equation to find the tree's height. ___

5. 5. A giraffe is 11 feet taller than a zebra. The giraffe is 17 feet tall. If $z$ is the zebra's height, which equation represents this situation?

   • A. $z + 11 = 17$
   • B. $z - 11 = 17$
   • C. $17 - z = 11$
   • D. $z + 17 = 11$

6. 6. After selling 36 cookies, a baker has 24 left. Let $c$ be the number of cookies he started with. Write the equation to find $c$. Equation: ___

7. 7. Kenji had 42 stamps. After buying some more, he now has 60 stamps. Which equation can be used to find the number of stamps, $s$, that he bought?

   • A. $s - 42 = 60$
   • B. $60 + 42 = s$
   • C. $42 + s = 60$
   • D. $s + 60 = 42$

8. 8. A blue scarf is 7 inches shorter than a red scarf. The blue scarf is 48 inches long. Let $r$ be the length of the red scarf. The equation is $r - 7 = $ ___.

9. 9. After losing 50 points in a video game, Sarah has 85 points. Let $p$ be her starting score. Write the equation to find her original score. Equation: ___