Math practice · Week 11 · Wednesday
I can explain each trade in my drawing.
Look: 268 + 457
- Ones: 8 + 7 = 15. I trade 10 dots for 1 stick. The amount is the same.
- Tens: 6 + 5 + 1 = 12. I trade 10 sticks for 1 square.
- Answer: 7 hundreds, 2 tens, 5 ones = 725.
Draw and solve. Then explain your trade.
- 347 + 286 = ____Answer: 633
- I traded ____ for ____ because ________.Answer: Answers vary. Look for: 10 ones for 1 ten (and 10 tens for 1 hundred) because 10 ones is the same as 1 ten.
- 731 − 458 = ____Answer: 273
- The number stayed the same when I opened a ten because ________.Answer: Answers vary. Look for: 1 ten is the same amount as 10 ones.
Challenge
- Why does 731 − 458 need two trades?Answer: 1 one is less than 8 ones, so open a ten. Then 2 tens are less than 5 tens, so open a hundred.
Second Grade · Week 11 · Wednesday · secondgrade.com