Estimation Strategies — Answer Key
Part A: Multiple Choice
Circle the best answer for each question.
1. A library has 4,872 books and adds 1,219 more. About how many books total?
A) 6,000
B) 8,000
C) 10,000
D) 12,000
5,000 plus 1,000 equals 6,000, the closest estimated total to the actual sum.
2. Which estimate of 412 × 29 is most reasonable?
A) 800
B) 12,000
C) 20,000
D) 60,000
Four hundred times thirty equals 12,000, the closest estimate to actual product.
3. A car drove 287 miles in 7 hours. About how many miles per hour?
A) 20
B) 30
C) 40
D) 50
280 divided by 7 equals 40, so speed estimate is about 40 miles hourly.
4. Which is the BEST estimate of 4.9 × 6.1?
A) 20
B) 24
C) 28
D) 30
Five times six equals 30, the closest reasonable estimate of this decimal product.
Part B: Fill in the Blank
Write the correct answer on each line.
1. Estimate 5,873 + 4,219 to nearest 1000: 10,000.
Six thousand plus four thousand equals 10,000, a strong estimate of the actual sum.
2. Estimate 38 × 49 by rounding to nearest 10: 2,000.
Forty times fifty equals 2,000, providing a quick estimated product easily.
3. Estimate 4,832 ÷ 8 using compatibles: 600.
4,800 divided by 8 equals 600, so 4,832 divided by 8 is about 600.
4. Estimate 6.78 × 4.2 to nearest whole: 28.
Seven times four equals 28, the closest whole-number estimated product here.
5. Estimate 9,128 - 3,876 to nearest 1000: 5,000.
Nine thousand minus four thousand equals 5,000, a tidy estimated difference.