# Lesson 7 Add and Subtract Within 1,000

Let’s add and subtract within 1,000.

## Warm-up Which One Doesn’t Belong: Add and Subtract Within 100

Which one doesn’t belong?

tens + ones + tens + ones

## Activity 1 Which Would You Rather Find?

Circle 2 sums or differences you think would be the most challenging to find. Find the value of one of these expressions. Show your thinking.

Choose 2 other expressions and find the values. Show your thinking.

## Activity 2 Add and Subtract Within 100

Find the value of each expression.

Choose one value that you think was less challenging to find. Explain.

Choose one value that you think was more challenging to find. Explain.