6th Grade Math Textbook, Progress

Addition and Subtraction of Decimals

1-9

A recent survey shows the amount

of liquid that the average person

consumes per year: 43.7 gal of juice,

37.3 gal of water, 27.3 gal of coffee,

21.1 gal of milk, and 8.1 gal of soda.

How many more gallons of juice,

water, and milk were consumed than

coffee and soda?

To find how many more gallons,

first add, then subtract.

First, find the amount of juice, water, and Next, find the amount of coffee and soda.

milk. Add: 43.7
37.3
21.1 Add: 27.3 
8.1

11 1


43.7 
27.3


37.3 
 8.1


21.1 
35.4


102.1

Then find how many more gallons of juice, water, and

milk were consumed than coffee and soda.

Subtract: 102.1 35.4

So 66.7 more gallons of juice, water, and milk were

consumed than coffee and soda.

Study these examples.

52.9045
 63 
0.7386
5.92

12 11


 0 52.9045


 063 .0000


 00 0.7386


 00 5.92 00


122.5631

Check. Change the order of the addends.

Add: 5.92 
0.7386 
 63 
52.9045 122.5631

?

?

??

9 11

0 10 1 11

1 02.1

 3 5.4

6 6.7

0.067 0.0095?

16

5 6 10


0.0 6 7 0

0.0 0 9 5


0.0 5 7 5

0

10

20

30

40

50

Juice Water Coffee

Liquid

Liquid Consumed Yearly

Amount (gal)

Milk Soda

2.0

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