Add 242 and 167. Use place value blocks if you need to. Hint: do you need to regroup ones or tens?
Let’s start by adding the ones, seven ones and two more. Seven, eight, nine. There are nine ones. Next, we move into the tens column, six tens and four tens. When we have 10 in a column, we need to regroup.
We need to regroup the 10 tens blocks into one hundreds block. So now there are no tens. And we have an extra hundred. Two hundreds plus one hundred and one more makes four. 242 and 167 makes 409.