Rounding
Round 628 to the nearest ten
630
Use rounding to estimate the sum of 23+99=____. Shows work
20+100 = 120
Use rounding to estimate the difference.
92-43=
90-40=50
Find the sum use break apart strategy. Show works
545+139=_____
684
Estimate. find the sum
679+482=
200
197
Round 704 to the nearest hundred
700
Estimate. Then find the sum
356+442=____
Estimate: 800
Sum: 798
Use rounding to estimate the differences. Show works
445-112=
400-100=300
Find the sum using place value strategy. Show works
437+184=_______
621
Estimate. Then find the difference.
537-123=_______
400
414
Round 58 to the nearest hundred
100
Estimate. Then find the sum
164+230=____
Estimate: 400
Sum: 394
Use rounding to estimate differences.
394 - 147=
300
Estimate. Then find the sum. Show works
39+243=
Sum: 282
Henry H. used 67+38=105 to check his subtraction. Which math problem could he be checking? Mark ALL that apply.
A. 67 - 38=____
B.105 - 67=____
C. 105 +38=____
D. 105 -88=_____
B
Emmett planted 77 daisies, 48 roses, and 39 tulips. About how many roses and tulip did he plant than daisies?
About 10 more
Andy collected 139 cans for recycling on Monday, and twice that number on Tuesday. How many cans did he collect on Tuesday? Show your work
278 cans
During October, 3rd grade decide to have a reading contest and the result as follow.
Ms. Vy's class - 273 books
Mrs. Hong's class - 402 books
Mrs. Ward's class - 247 books
Select true or false (T/F) for each statement:
1. Ms. Hong's class read about 100 more books than Ms. Vy's class. T/F
2. The 3 classes read over 900 books altogether. T/F
3. Mrs. Ward's class read about 50 fewer books than Ms. Vy's class. (T/F)
4. Mrs. Hong's and Mrs. Ward's class read about 700 books. (T/F)
1. True
2. True
3. False
4. False
Harper Lynn was making paper flowers for friends. In January, she gave away 246 paper flowers to her family. In February, she gave away 418 paper flowers to her friends. In March, she gave away 349 paper flowers to her neighbors. How many more flowers did she give away in January than March?
103 paper flowers
Marcus has 402 pieces in a building set. He uses 186 pieces to build a house. How many pieces does he have left? Show your work.
216 pieces;
402 - 186=216
Isaac sold 237 cups of lemonade at his lemonade stand. What is 237 rounded to the nearest ten? Include the unit label.
240 cups
There are 294 boys and 332 girls in the NBC school. How many students are in the school?
626 students
Hannah sold 486 muffins at the bake sale. Sawyer sold 287 muffins. Sawyer estimates that he sold 200 fewer muffins than Hannah. How did he estimate? Explain.
Sawyer rounded to the nearest hundred.
He rounded 486 to 500 and 287 to 300.
Then he subtracted 500-300= 200
Delaney was making paper flowers for friends. In January, she gave away 246 paper flowers to her family. In February, she gave away 518 paper flowers to her friends. In March, she gave away 349 paper flowers to her neighbors. How many paper flowers did she give away in January and February?
764 paper flowers.
Madi solved this problem. She says the difference is 214. Explain the mistake Madi made. What is the correct difference?
352-148=
She did not combine the right place value numbers. She needs to re-group 1 ten as 10 ones to subtract 48 from 52. The difference is 204