Nagwa uses cookies to ensure you get the best experience on our website. Learn more about our Privacy Policy.

Start Practicing

Worksheet: Estimating Sums of Three-Digit Numbers

Q1:

Look at how Amelia estimated this sum.

Estimate the sum of 6 1 5 + 2 0 9 by rounding both numbers to the nearest ten.

Estimate the sum of 2 6 2 + 1 4 7 by rounding both numbers to the nearest ten.

Q2:

Look at how Noah rounded to estimate this sum.

Round the numbers in this sum to the nearest hundred.

  • A
  • B
  • C
  • D

Calculate the estimate.

Q3:

Look at how Scarlett rounded to estimate this sum.

Round the numbers in this sum to the nearest ten.

  • A
  • B
  • C
  • D

Calculate the estimate.

Q4:

Look at this calculation.

Estimate the answer by rounding both numbers to the nearest hundred.

Estimate the answer by rounding both numbers to the nearest ten.

Find the exact answer.

Tip: Use the estimates to see if your answer is sensible.

Q5:

Look at how James estimated the sum.

Estimate the sum of 7 3 1 + 1 1 9 by rounding both numbers first to the nearest hundred.

Estimate the sum of 4 7 5 + 1 2 6 by rounding both numbers first to the nearest hundred.

Q6:

Emma won 586 tickets at the fair. Her sister won 379.

Pick the best estimate for the total number of tickets that they won.

  • A900
  • B800
  • C600
  • D 1 000
  • E200