Write two addition problems. Each addend must be three digits. Write and solve a problem where you need to regroup to make a ten or a hundred. Explain why you needed to regroup.
1) 347 + 586
347
+ 586
------
933
2) 425 + 378
425
+ 378
------
803
If we add 5 and 8 in the ones place in the second problem, we get 13. Since we cannot have a two-digit number in a single place value, we have to regroup and carry over the 1 to the tens place. This allows us to properly add the numbers together and get the correct sum.