## Envision Math 5th Grade Textbook Answer Key Topic 2.4 Adding and Subtracting

**Adding and Subtracting**

How can you add and subtract whole numbers?

What was the total number of motor vehicles made in the United States and Japan in one year?

Choose an Operation

Add to join groups.

Find 11,989,387 + 10,511,518.

Estimate:

12,000,000 + 11,000,000 = 23,000,000

Another Example

How can you subtract across zeros?

Find 5,002 – 2,684. Since addition and subtraction have an inverse relationship, check your subtraction by adding

Step 1

Step 2

Check

**Explain It**

Question 1.

Explain the regrouping in Step 1 of the subtraction example above.

Answer:

Question 2.

Why can you check a subtraction problem by adding?

Answer:

Step 1

Line up numbers by place value. Add the ones, tens, and hundreds.

Step 2

Continue adding. Regroup if needed. Insert commas in the sum to separate periods.

The sum is reasonable since the estimate was 23,000,000.

In one year a total of 22,500,905 vehicles were made

**Guided Practice***

Do you know HOW?

Add.

Question 1.

5,741 + 31,018

Answer:

Question 2.

7,110 + 499

Answer:

Subtract.

Question 3.

9,234 – 2,387

Answer:

Question 4.

110,652 – 8,600

Answer:

Do you UNDERSTAND?

Question 5.

Writing to Explain In Step 2 of the example above, explain how you regrouped the tens place.

Answer:

Question 6.

In the example above, how many cars did the United States and Germany make altogether?

Answer:

**Independent Practice**

In 7 through 12, add.

Question 7.

7,469 + 8,374

Answer:

Question 8.

19,335 + 24,281

Answer:

Question 9.

40,742 + 22,597

Answer:

Question 10.

102,369 + 60,320

Answer:

Question 11.

18,269 + 109,347

Answer:

Question 12.

75,977 + 24,683

Answer:

In 13 through 18, subtract. Check your answer by adding.

Question 13.

4,002 – 3,765

Answer:

Question 14.

58,005 – 1,098

Answer:

Question 15.

113,300 – 1,774

Answer:

Question 16.

454,900 – 33,870

Answer:

Question 17.

31,483 – 29,785

Answer:

Question 18.

103,558 – 64,671

Answer:

Question 19.

Reasoning Why should you estimate before you find the sum or difference of large numbers?

Answer:

Question 20.

About 66,150,000 households in the U.S. have cats and about 58,200,000 households have dogs. About how many more households have cats than dogs?

Answer:

Question 21.

Write a Problem Use 1,400 and 986 to write a real-world addition problem.

Answer:

Question 22.

Humans are born with 350 bones. Some of these bones fuse together as humans grow. Adults only have 206 bones. How many more bones does a baby have than an adult?

Answer:

Question 23.

Find each sum and difference. Write >, <, or = for each .

a. 1,233 + 486 2,200 – 481

b. 193 + 233 309 + 118

c. 544 + 4,732 2,512 + 1,930

d. 9,491 – 6,230 7,020 – 3,759

The table at the right shows the amount of time (rounded to the nearest hour) that astronauts have spent in space for several space programs.

Answer:

Question 24.

For the five space programs listed, what is the total number of hours astronauts spent in space?

A. 14,608 hours

B. 17,621 hours

C. 19,988 hours

D. 20,038 hours

Answer:

Question 25.

How much longer did astronauts in the Space Shuttle program spend in space than all of the other programs combined?

A. 631 hours

B. 2,194 hours

C. 4,776 hours

D. 12,407 hours

Answer:

Question 26.

Lisa has a basket of 17 tomatoes. She makes sauce with 9 tomatoes. If Lisa wants to split up the rest between 3 friends and herself, how

many tomatoes does each person get?

Answer:

Question 27.

There are about 44,000 farms in Florida and about 38,000 farms in New York. Are the total number of estimated farms in Florida and

New York greater or less than 100,000?

Answer:

**Stop and Practice**

Find each sum. Estimate to check if the answer is reasonable.

Question 1.

Answer:

Question 2.

Answer:

Question 3.

Answer:

Question 4.

Answer:

Question 5.

Answer:

Question 6.

Answer:

Question 7.

Answer:

Question 8.

Answer:

Find each difference. Estimate to check if the answer is reasonable.

Question 9.

Answer:

Question 10.

Answer:

Question 11.

Answer:

Question 12.

Answer:

Question 13.

Answer:

Question 14.

Answer:

Question 15.

Answer;

Question 16.

Answer:

Question 17.

Answer:

Question 18.

Answer:

Error Search Find each sum or difference that is not correct.

Write it correctly and explain the error.

Question 19.

Answer:

Question 20.

Answer:

Question 21.

Answer:

Question 22.

Answer:

Question 23.

Answer:

**Number Sense**

Estimating and Reasoning Write whether each statement is true or false. Explain your reasoning.

Question 24.

The difference of 32,076 and 21,894 is closer to 10,000 than 11,000.

Answer:

Question 25.

The sum of 10,323 and 9,769 is greater than 19,000 but less than 21,000.

Answer:

Question 26.

The sum of 8,242 and 4,031 is less than 12,000.

Answer:

Question 27.

The difference of 6,712 – 3,503 is 3 more than 3,212.

Answer:

Question 28.

The sum of 405 + 319 is 5 more than 719.

Answer:

Question 29.

The difference of 8,764 – 1,843 is greater than 8,000.

Answer: