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Add and subtract within 100: FAQ

Frequently asked questions about adding and subtract within 100.

Why do we need to learn how to add and subtract within 100?

Adding and subtracting within 100 is important because it builds a foundation for more complex math later on. Plus, it's helpful for everyday tasks like counting money or figuring out how many items you have.

How can we use place value blocks to help us add and subtract?

Place value blocks can help us visualize the numbers we're working with. We can use the blocks to break down a number into tens and ones, and then use those parts to help us add or subtract.

What are some strategies for adding within 100?

One strategy is to break apart one of the numbers and make tens. For example, to add 58+7, we can break apart the 7 into 2 and 5. Then, we can add 58+2 to make 60, and add the remaining 5 to get a final answer of 65.

What are some strategies for subtracting within 100?

One strategy is to count backwards on a number line. For example, to subtract 5 from 42, we can start at 42 on the number line and count backwards five spaces to land on 37.

What are some tips for solving word problems?

We should always read the problem carefully, and make sure we understand what it's asking us to do. We can underline or highlight important information, and draw pictures or use diagrams to help us visualize the problem. We can also write out equations to help us organize our work.

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