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### Course: 2nd grade > Unit 3

Lesson 1: Visually adding within 100- Add and subtract within 100: FAQ
- Adding 2-digit numbers without regrouping
- Understanding place value when adding ones
- Understanding place value when adding tens
- Adding with regrouping
- Add within 100 using place value blocks
- Addition and subtraction with number lines
- Add within 100 using a number line

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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.