Adding, Subtracting, and Multiplying Decimals

Adding, Subtracting, Multiplying, and Dividing Decimals

Adding Decimals

Adding Decimals

Steps to adding decimals:

1. Line up your decimals because place value matters!

2. Bring the decimal point straight down

3. Fill in blank spaces with zeros

4. Add to get your answer

​

​Teacher Model!

3.4 + 2.17

Give it
a try!

Multiple Choice

Isaac has $19.55 in his wallet. His brother gave him $7.12 more. How much money does Isaac have in total?

• $24.32

• $12.43

• $26.67

• $16.67

Multiple Choice

The fence surrounding John’s house measured 74.56 inches. If it was extended by 25.3 inches, what is the new height of the fence?

• 86.54 inches

• 49.26 inches

• 77.09 inches

• 99.86 inches

Multiple Choice

The weight of a crate of potatoes is 52.34 pounds. The weight of a crate of onions is 29.12 pounds. What is the sum of the two weights?

• 81.46 pounds

• 71.46 pounds

• 23.22 pounds

• None of the above

Multiple Choice

Paige was measuring how much taller she got over two years. In the first year she grew 4.62 cm. In the second year she grew 7.7 cm. How much taller did she get altogether?

• 5.39 cm

• 11.78 cm

• 12.32 cm

• 12 cm

Subtracting Decimals

Subtracting Decimals

Steps to subtracting decimals:

1. Line up your decimals because place value matters!

2. Bring the decimal point straight down

3. Fill in blank spaces with zeros

4. Subtract to get your answer

​

​Teacher Model!

15.1 - 7.95

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a try!

Multiple Choice

Mr. Maclane drove 577.2 miles. Ms. Lopez drove 165.4 miles. About how many more miles did Mr. Maclane drive than Ms. Lopez?

• 400 miles

• 300 miles

• 800 miles

• 700 miles

Multiple Choice

Jerry bought 6.95 lbs of cherry and lime jelly beans for his birthday party. If 1.75 lbs were cherry flavor, how many pounds were lime flavor?

• 8.7 lbs

• 5.2 lbs

• 7.70 lbs

• 6.7 lbs

Multiple Choice

Sam scored 399.8 points at a track meet. Eric scored 462.25 points at the same track meet. What is the difference in the amount of points they scored?

• 862.05 points

• 502.23 points

• 5,022.3 points

• 62.45 points

Multiple Choice

Vanessa downloaded two apps which were 17.73 kb total. If one app was 8 kb, how big was the other app?

• 9.73 kb

• 17.65 kb

• 25.73 kb

• 9.00 kb

Multiplying Decimals

Multiplying Decimals

Steps to multiplying decimals:

1. Line up your digits against the "wall"

2. Multiply like usual (IGNORE the decimals)

3. Count the number of decimals places in TOTAL

4. Place a decimal at the end of your product

5. Move the decimal in your product to the left based on the total amount of decimal places you had.

​

​Teacher Model!

Give it
a try!

Multiple Choice

Hannah bought 3.4 pounds of apples. She paid $.89 per pound. How much did Hannah pay for the apples?

• $3.00

• $3.03

• $3.01

• $3.02

Multiple Choice

To take an Uber, Aidan must pay $2.25 per mile. He wants to go to the movies which is 8.7 miles from his house. How much will it cost Aidan to take an Uber from his house to the movie theater?

• $19.58

• $19.57

• $18.58

• $18.57

Multiple Choice

Celeste bought 4.6m of fabric that cost $3.57 per meter. What was her total cost?

• $1.64

• $16.42

• $16.56

• $165.60

Multiple Choice

Sarah jogged 4.8 miles each day for the last 22 days. How many miles did Sarah jog in total?

• 110 miles

• 88.16 miles

• 105.6 miles

• 26.8 miles

Dividing Decimals

Dividing Decimals

Steps to dividing decimals:

1. Set up your equation

2. Move the decimal from the dividen, vertical on top in the quotient

3. Divide like normally to get your quotient

​

​Teacher Model!

Give it
a try!

Multiple Choice

An expression is shown below:

$$9.45\div15$$

What is the quotient?

• 6.3

• 0.03

• 0.63

• 0.6

Multiple Choice

The 3 computer monitors in a classroom use a total of 0.87 watt of electricity. Each monitor uses the same number of watts.

How many watts does each monitor use?

• 2.9 watts

• 0.261 watts

• 2.61 watts

• 0.29 watts

Math Response

A resturant bill was paid equally by 7 friends. The bill was $99.96. How much money in dollars and cents did each person pay?

Type answer here

Correct Answer: 14.28

Deg^°

Rad

Multiple Choice

A cafeteria worker used 8.05 kilograms of meat to make 35 lunches. Each lunch had the same amount of meat.

What was the mass in kilograms of the meat in each lunch?

• 2.03 kg

• 0.23 kg

• 0.023 kg

• 2.3 kg

Bonus
Questions!

Multiple Choice

How much did Rebecca pay for these 8 air filters?

• $80.70

• $143.10

• $128.10

• $75.60

Multiple Choice

How much money did Kassidy earn walking and bathing dogs last weekend?

• $97.25

• $1,411.00

• $194.50

• $131.25

Multiple Choice

What is the price of the items Nakita bought?

• $6.95

• $10.45

• $9.65

• $12.65

Multiple Choice

What is the value of the expression shown?

4(4.5-2(1.2))

• 8.4

• 15.6

• 12

• 19.2