Addition Within 20 (Number Lines) — Answer Key
Part A: Trace the Words
Trace each word carefully by following the dotted lines.
1. plus
2. sum
3. add
4. total
5. equal
6. more
Part B: Fill in the Blank
Write the missing word or number on each line.
1. 8 + 5 = 13
Start at 8 on the number line and jump 5 spaces forward to land on 13.
2. 7 + 6 = 13
Start at 7 and count up 6 more: 8, 9, 10, 11, 12, 13. You land on 13.
3. 9 + 4 = 13
From 9, hop 4 spaces forward on the number line: 10, 11, 12, 13. The answer is 13.
4. 6 + 8 = 14
Start at 6 and jump 8 spaces ahead to reach 14. You can also start at 8 and jump 6 to get the same answer.
Part C: True or False?
Read each statement. Circle True or False.
1. 9 + 7 = 16
True False
True. Starting at 9 and counting up 7 gives you 16, so this equation is right.
2. 8 + 6 = 15
True False
False. 8 + 6 actually equals 14, not 15. Count up 6 from 8 to check.
3. 5 + 9 = 14
True False
True. Starting at 5 and jumping 9 spaces on the number line lands you on 14.