Show:
Decimal Rule
Addition of Decimals
Subtraction of Decimals
Multiplication of Decimals
Division of Decimals
100
How do you add decimals?
You line up the decimals and then add the numbers.
100

5.9 + 3.5 =

9.4

100
3.95 - 2.7 =
1.25
100
.6 x 2.1 =
1.26
100
.25 divided by .05 =
5
200
How do you subtract decimals?
You line up the decimals and then subtract the numbers.
200

8.34 + 5.48 =

13.82

200
95.29 - 1.3 =
93.99
200
4.25 x 21 =
89.25
200
3.87 divided by .9 =
4.3
300
What do you do if there are not enough digits in the top number to subtract a problem?
You have to add on zero's.
300

55.23 + 43.22 =

98.45

300
125 - .68 =
124.32
300

36.5 x 5.2 =

189.8

300

18.4 divided by 3.2 =

5.75

400
How do you multiply decimals?
You multiply the numbers and then you count how many spaces there are to the right of the decimals and count them over to the left in the answer.
400

564.56 + 345.543= 

910.103

400

84.56 - 43.34 = 

41.22

400

82.03 x 8.0 =

656.24

400

402.60 divided by 3.3  =

122

500
How do you divide decimals?
You have to get rid of the decimals on the outside by moving the decimals on the inside. Then bring the decimal straight up and divide normally.
500

Cassidy weighed two colored metal balls during a art class. The purple ball weighed 45.6 pounds and the yellow ball weighed 35.7 pounds. If Cassidy places both balls on the scale at the same time, what will the scale read?

45.6 + 35.7 = 81.3

The scale will read 81.3 pounds.

500

Jennifer runs 4.8 kilometers every morning. One day, she runs 1.3 kilometers and then stops to take a break. How much further does Jennifer have left to run?

4.8 - 1.3 = 3.5 

Jennifer has 3.5 kilometers left to run.

500

Matthew grows wheat on his farm. One of his fields produced 66.8 bushels of wheat this year. If wheat is currently selling for $5.40 per bushel, how much will Matthew earn from this field?

66.8 x 5.40 = 360.72

Matthew will earn $360.72.

500

Torin adopted a cat from a rescue shelter. He needs to buy some cat litter, so he compares prices at different stores. He finds the best deal at Fluffy Felines Pet Shop, which sells a 20.0 pound jug of cat litter for $8.60. How much does the cat litter cost per pound?

8.60 / 20.0 = 0.43

The cat litter costs $0.43 per pound.