Rounding to Nearest 10 and 100 — Answer Key
Part A: Multiple Choice
Circle the best answer for each question.
1. What is 276 rounded to the nearest hundred?
A) 200
B) 270
C) 280
D) 300
347 rounded to the nearest hundred is 300 because the tens digit (4) is less than 5, so we round down.
2. Sara has 47 stickers and buys 33 more. About how many stickers does she have if you round to the nearest ten?
A) 70
B) 80
C) 90
D) 100
78 rounded to the nearest ten is 80 because the ones digit (8) is 5 or greater, so we round up.
3. Which number rounds to 500 when rounded to the nearest hundred?
A) 432
B) 549
C) 552
D) 448
549 rounds to 550 because the ones digit (9) is 5 or greater, so we round up to 550.
4. What is the best estimate for 78 - 21 when both numbers are rounded to the nearest ten?
A) 50
B) 60
C) 70
D) 80
64 rounded to the nearest ten is 60 because the ones digit (4) is less than 5, so we round down.
Part B: Fill in the Blank
Write the correct answer on each line.
1. 365 rounded to the nearest hundred is 400.
365 rounded to the nearest hundred is 400 because the tens digit (6) is 5 or greater, so we round up.
2. 44 + 37 is about 80 when each number is rounded to the nearest ten.
44 rounds to 40 and 37 rounds to 40, so 40 + 40 = 80.
3. 891 rounded to the nearest ten is 890.
891 rounded to the nearest ten is 890 because the ones digit (1) is less than 5, so we round down.
4. When rounding 650 to the nearest hundred, the answer is 700.
650 rounded to the nearest hundred is 700 because the tens digit (5) is 5 or greater, so we round up.
5. 52 - 28 is about 20 when each number is rounded to the nearest ten.
52 rounds to 50 and 28 rounds to 30, so 50 - 30 = 20.