Rounding to Nearest 10 and 100 — Answer Key
Part A: Fill in the Blank
Write the missing word or number on each line.
1. 56 rounded to the nearest ten is 60.
56 rounded to the nearest ten is 60 because the ones digit (6) is 5 or greater, so we round up.
2. 423 rounded to the nearest hundred is 400.
423 rounded to the nearest hundred is 400 because the tens digit (2) is less than 5, so we round down.
3. 85 rounded to the nearest ten is 90.
85 rounded to the nearest ten is 90 because the ones digit (5) is 5 or greater, so we round up.
4. 749 rounded to the nearest hundred is 700.
749 rounded to the nearest hundred is 700 because the tens digit (4) is less than 5, so we round down.
5. 32 + 49 is about 80 when you round each number to the nearest ten first.
32 rounds to 30 and 49 rounds to 50, so 30 + 50 = 80.
6. 167 rounded to the nearest ten is 170.
167 rounded to the nearest ten is 170 because the ones digit (7) is 5 or greater, so we round up.
7. 350 rounded to the nearest hundred is 400.
350 rounded to the nearest hundred is 400 because the tens digit (5) is 5 or greater, so we round up.
8. 88 - 31 is about 60 when you round each number to the nearest ten.
88 rounds to 90 and 31 rounds to 30, so 90 - 30 = 60.
9. 215 rounded to the nearest hundred is 200.
215 rounded to the nearest hundred is 200 because the tens digit (1) is less than 5, so we round down.
Part B: Matching
Match each item on the left to the correct answer on the right.
1. Match each item to its correct answer.
67
→ 70
100
450
→ 500
200
234
→ 200
70
95
→ 100
500
67 rounds to 70 (nearest ten), 450 rounds to 500 (nearest hundred), 234 rounds to 200 (nearest hundred), and 95 rounds to 100 (nearest ten).