Word Problems: Add & Subtract Within 20 — Answer Key
Part A: Show Your Work
These problems may need two steps. Use the box to show your work.
1. Ava has 8 beads. She finds 6 more, then gives 3 to her sister. How many beads does Ava have now?
Answer: 11 beads
First add: 8 + 6 = 14 beads. Then subtract: 14 - 3 = 11 beads left.
2. There are 15 crayons in a box. Ben takes 7 and then puts 4 back. How many crayons are in the box now?
Answer: 12 crayons
First subtract: 15 - 7 = 8 crayons. Then add: 8 + 4 = 12 crayons.
Part B: Solve Without a Work Box
Read each problem and write the answer on the line.
1. Zoe has 13 grapes. Kim has 7 grapes. How many more grapes does Zoe have than Kim?
Answer: 6 grapes
Subtract to find the difference: 13 - 7 = 6 more grapes at the start.
2. A bus has 18 seats. If 9 seats are taken, how many seats are empty?
Answer: 9 seats
Subtract the empty seats: 18 - 9 = 9 seats are taken.
Part C: Think About It
Write the missing number or word on each line.
1. If 8 + 6 = 14, then 14 - 6 = 8.
Addition and subtraction are related: since 8 + 6 = 14, taking 6 away from 14 gives back 8.
2. To find 'how many more,' you should subtract.
The phrase 'how many more' asks for the difference between two numbers, which means subtract.
3. 17 - 9 = 8
When you subtract 9 from 17, you get 8.
4. If Sara has 5 fewer stickers than Tom, and Tom has 12, Sara has 7.
Subtract to find Sara's amount: 12 - 5 = 7 stickers.