Rounding & Estimation
Round 347 to the nearest ten.
350
Solve: 235 + 142
377
Solve: 487 − 235
252
Write 458 in expanded form.
400 + 50 + 8
Mia has 20 stickers. She gets 15 more and gives away 8. How many remain?
27
Round 682 to the nearest hundred.
700
Solve: 367 + 258
625
Solve: 563 − 247
316
What number is 600 + 70 + 9?
679
There are 5 bags with 6 apples in each. The teacher adds 12 more apples. How many apples are there?
42
Estimate 426 + 281 by rounding to the nearest hundred.
400 + 300 = 700
Solve: 485 + 276. Show your regrouping.
761
Solve: 602 − 178.
424
Use expanded form to solve 324 + 253.
577
A school has 450 pencils. It gives 125 to third grade and 175 to fourth grade. How many remain?
150
Estimate 793 − 358 by rounding to the nearest ten.
790 − 360 = 430
Solve: 596 + 187. Explain where you regrouped
783
Solve: 805 − 467.
338
If 345 + 278 = 623, what is 623 − 278?
345
There are 8 boxes of crayons with 9 crayons in each box. Students use 27 crayons. How many are left?
45
A student says 389 + 412 = 501. Use rounding to explain whether the answer is reasonable.
No. 400 + 400 = 800, so 501 is not reasonable.
A student solved 478 + 356 and got 724. Find the mistake and explain the correct answer.
834. The student made an error while regrouping.
A student says 700 − 386 = 486. Is the student correct? Explain using subtraction or addition.
No. The correct answer is 314. Check: 386 + 314 = 700.
Use expanded form to solve 756 − 324. Explain how you decomposed the numbers.
432
A library has 375 books. It receives 248 new books, then students check out 186 books. How many books remain? Write an equation with an unknown.
437 books. 375 + 248 − 186 = □