Adding Four Two-Digit Numbers by Decomposing

This lesson teaches how to add four two-digit numbers by decomposing them into tens and ones. It begins with an explanation of decomposing and the commutative property of addition. Two examples are provided, involving the addition of numbers representing tomatoes picked by a farmer over two weeks. Each example demonstrates breaking down numbers into tens and ones, adding them separately, and then combining the sums to find the total. The lesson concludes with a summary of the decomposing method.

Describe the process of adding the numbers 33, 24, 17, and 12 by decomposing them.

What was the total number of tomatoes picked by the farmer in the second week?