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## 2nd grade

### 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, plus, 7, we can break apart the 7 into 2 and 5. Then, we can add 58, plus, 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.

## Want to join the conversation?

- what is 8 times 92?(5 votes)
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- what is 7804+5960(2 votes)
- what is 23-24?(3 votes)
- Good question for 2nd grade! We cannot solve this problem using only the numbers learned up to 2nd grade, but we can solve it using numbers from a higher grade level (about 5th or 6th grade) called negative numbers.

Because 23-24 means subtracting a larger number from a smaller number, and 24 is 1 more than 23, the answer is called -1. This is read as "minus 1" or "negative 1".

Have a blessed, wonderful day!(1 vote)

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