Practice choosing compatible numbers that are easy to work with mentally, then use them to estimate answers.
Read each problem carefully. Choose compatible numbers that are easy to calculate with. Show your work in the space provided.
Use friendly numbers to estimate sums, differences, products, and quotients
Math - Grade 4-5
- 1
Estimate 398 + 204 using compatible numbers. Explain which numbers you used.
- 2
Maya has 487 stickers, and her friend gives her 312 more. Use compatible numbers to estimate how many stickers Maya has now.
- 3
Estimate 721 - 298 using compatible numbers. Show your thinking.
- 4
A school library has 1,206 books. Students check out 398 books. Estimate how many books are left using compatible numbers.
- 5
Estimate 49 x 21 using compatible numbers. Explain your estimate.
- 6
A bus holds 38 students. About how many students can ride on 9 buses? Use compatible numbers.
- 7
Estimate 2,412 ÷ 6 using compatible numbers. Show how you chose your numbers.
- 8
A farmer packs 1,785 apples equally into 9 boxes. Estimate how many apples are in each box using compatible numbers.
- 9
Choose the better compatible number estimate for 603 + 198: 600 + 200 or 500 + 100. Explain your choice.
- 10
Estimate 4,089 - 1,987 using compatible numbers.
- 11
A theater sold 52 tickets for each of 18 shows. Estimate the total number of tickets sold using compatible numbers.
- 12
A student estimates 3,152 ÷ 8 by using 3,200 ÷ 8. Is this a good compatible number estimate? Explain why or why not.