When you you multiply when do you need to regroup?

Answer 1

You need to regroup when you add the numbers together and they add up to a number that is ten or more.

For example: 1

164

+518

_____

682

If it is over ten, take the first digit of the number and put it above the next number. Then, add that number onto the sum of the other digits underneath it.

Answer 2

you need to regroup when the bottom number is bigger than the top number