To review these concepts, go to Decimal Word Problems Study Guide.

**Decimal Word Problems Practice Questions**

**Practice 1**

**Problems**

- Round 18.649 to the nearest hundredth.
- Subtract: 648.99 – 21.48.
- Add: 45.6 + 32.05.
- Multiply: 2.8 × 6.51.
- Divide: 230.3 ÷ 23.5.

**Solutions**

- 18.65
- 627.51
- 77.65
- 18.228
- 9.8

**Practice 2**

**Problems**

- Andy had a balance of $65.58 in his bank account. He then paid a bill for $42.14. How much money did he have left in his account after he paid the bill?
- Elise bought 12 cans of dog food. The price for the cans was 3 for $4.69. How much money did she spend on dog food?
- At a movie theater, a box of popcorn cost $4.50, and a soda cost $2.00. If Sandra bought exactly 5 items for her family and spent $15.00, what did she buy?
- Tim swam four laps of the pool in 140.8 seconds. If he swam at the same pace the entire time, how long did it take him to swim one lap?
- Ken bought 12.5 gallons of gasoline at $3.12 a gallon. What is the total amount of money he spent on gasoline?

**Solutions**

*Read and understand the question*. This problem asks for the total amount in a bank account after a bill has been paid. The amount in the account to start and the amount of the bill are given.*Read and understand the question*. This question asks for the total amount of money spent on 12 cans of dog food. The price for 3 cans is given.*Read and understand the question*. This question is looking for the exact items that were bought when the price of each is given, along with the fact that there are exactly 5 items purchased for a total of $15.00.*Read and understand the question*. This question is looking for the length of time it took to swim one lap when the time to swim 4 laps is given.*Read and understand the question*. This question is looking for the total amount spent on gasoline. The number of gallons and the price per gallon are given.

*Make a plan*. The key phrase *how much does he have left* tells you to subtract the amount of the bill from the amount in the account.

*Carry out the plan*. Subtract $65.58 – $42.14. Be sure to line up the decimal points. The answer is $23.44.

*Check your answer*. Check your answer by working backward. Begin with the new balance of the account and add the amount of the bill to see if it is equal to the original amount in the bank account. $23.44 + $42.14 = $65.58. This answer is checking.

*Make a plan*. Because 3 × 4 = 12, multiply the price for 3 cans by 4 to find the total amount spent on 12 cans.

*Carry out the plan*: $4.69 × 4 = $18.76. She spent a total of $18.76 on 12 cans.

*Check your answer*. Check this solution by working backward. Divide $18.76 by 4. This is equal to $4.69, which is the cost of 3 cans. Four groups of 3 cans are equal to 12 cans, so this answer is checking.

*Make a plan*. Use the strategy of guess and check and your knowledge of decimals to find the numbers of each item that were bought.

*Carry out the plan*. Start with 1 box of popcorn and 4 sodas. Because the cost of soda is $2.00, then 4 sodas would be $8.00: $4.50 + $8.00 = $12.50, which is too low. You may now realize that an odd number of boxes of popcorn cannot result in a whole dollar amount, so try even amounts of popcorn.

Try 4 boxes of popcorn and 1 soda. This is a total of 4 × $4.50 = $18, which is too high even before the 1 soda is added.

Try 2 boxes of popcorn and 3 sodas. This is a total of 2 × $4.50 = $9.00 and 3 × $2.00 = $6.00: $9.00 + 6.00 = $15.00. This is the correct solution.

*Check your answer*. Check your answer by making sure that the answer fits the details in the problem. She bought a total of 5 items for a total of $15.00, so this answer is checking.

*Make a plan*. Divide the total time for the 4 laps by 4 to find out the time for 1 lap.

*Carry out the plan*. The total time was 140.8 seconds: 140.8 divided by 4 equals 35.2 seconds. At the same pace, it took Tim 35.2 seconds to complete 1 lap.

*Check your answer*. Check this solution by multiplying 35.2 by 4 laps: 35.2 × 4 = 140.8. This question is checking.

*Make a plan*. Multiply the number of gallons by the price per gallon to find the total money spent on gasoline.

*Carry out the plan*. $3.12 multiplied by 12.5 is equal to $39.00. Ken spent a total of $39.00 on gasoline.

*Check your answer*. Check this result by using inverse operations. Divide the total amount spent by the price per gallon: $39.00 ÷ $3.12 = 12.5 gallons. This question is checking.

### Ask a Question

Have questions about this article or topic? Ask### Related Questions

#### Q:

#### Q:

#### Q:

#### Q:

### Popular Articles

- Kindergarten Sight Words List
- First Grade Sight Words List
- Child Development Theories
- 10 Fun Activities for Children with Autism
- Social Cognitive Theory
- Signs Your Child Might Have Asperger's Syndrome
- Why is Play Important? Social and Emotional Development, Physical Development, Creative Development
- Theories of Learning
- Definitions of Social Studies
- A Teacher's Guide to Differentiating Instruction