# Worksheet: Part–Whole Bar Models: Numbers up to 100

In this worksheet, we will practice solving one-step addition and subtraction problems with numbers up to 100 by drawing a part–whole bar model.

**Q1: **

Emma is trying to solve this word problem:

There were 41 birds in a tree. 15 of them flew away. How many birds are in the tree now? Emma said the answer was . What did she do wrong? What is the correct answer?

- AShe added when she should not have. The answer is 41.
- BShe added when she should have subtracted. The answer is .
- CShe added when she should have subtracted. The answer is .
- DShe made a mistake in the addition. The answer is .
- EShe added when she should have subtracted. The answer is .

**Q2: **

Ethan and Elizabeth were building houses out of blocks. Ethan used 36 blocks. Elizabeth used 51 blocks. How many blocks did they use?

Will the answer be bigger or smaller than the numbers in the question?

- Abigger
- Bsmaller

Do you need to add or subtract to find the answer?

- Asubtract
- Badd

Find out how many blocks they used.

**Q3: **

Benjamin has 62 blocks to build with. He used 29 blocks to build one house. He wants to build a second house with the leftover blocks.

Is the number of leftover blocks bigger or smaller than 62?

- Asmaller
- Bbigger

Do you need to add or subtact to find how many blocks he has left to build the second house?

- Asubtract
- Badd

How many blocks are left to build the second house?

**Q4: **

James is trying to solve this word problem:

There were 37 fish in a pool at the bottom of a waterfall. 12 fish swam down the waterfall into the pool. How many fish are in the pool now?

James said the answer was . What did he do wrong? What is the correct answer?

- AHe subtracted when he should have added. The answer is .
- BHe made a mistake in subtracting. The answer is .
- CHe subtracted when he should have added. The answer is .
- DHe subtracted when he should have added. The answer is .
- EHe subtracted when he should not have. The answer is 12.

**Q8: **

Subtract 30 from 50 to finish this part-part-whole picture.

**Q9: **

Ethan and Mia are making a bridge out of blocks. They choose 23 green blocks and 30 red blocks. How many blocks do they use altogether?

**Q10: **

One bag has 61 balls, and we add 9 more. How many balls do we have in the bag?

**Q11: **

46 children are on a school bus. After some time, 7 more get on the bus. How many children are on the bus now?

**Q13: **

I am a number. If you subtract me from 64, you get 53. What number am I?

**Q14: **

Scarlett had 46 emails in her inbox. She deleted 41 of them. How many emails are left in her inbox?

**Q15: **

A supermarket has two different kinds of chocolate bars. If there are 24 bars of the first kind and 49 of the second, what is the total number of chocolate bars in the supermarket?

**Q16: **

A farmer has 43 ducks and 24 hens. Find the total number of birds that he has.

**Q17: **

On Monday morning, 60 boys and 58 girls went to the school library. In the afternoon, 84 boys and 25 girls went to the school library. How many girls went to the library on Monday?

**Q19: **

Matthew has 69 marbles. His friend gives him 4 more. How many marbles does he have now?

**Q20: **

There were 98 birds in a tree. 36 flew away. How many are left?