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
58.9 + 3.04 =
61.94
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
.004 + 5.1 =
5.104
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 place  zero's so that all the places have a digit. 

300
.9843 + 2.67 =
3.6543
300
125 - .68 =
124.32
300
.03 x .03 =
.0009
300
.425 divided by .005 =
85
400

How do you multiply decimals?

You multiply the numbers,  count the number of decimal places in each factor.  Add that and count them over to the left in the product

400
5 + 2.78 + .030 =
7.81
400
.468 - .059 =
.409
400
2.003 x .05 =
.10015
400
.848 divided by 8 =
.106
500

How do you divide decimals?

The divisor(outside) must be a whole number.  Move the decimal to the right until it is a whole number,   on move  the decimal the same number of spaces on the dividend, inside. divide as normal. 

500
8.07 + .0976 + 23.3 + 48 =
79.4676
500
5.45 - 3.799 =
1.651
500
.312 x 1.67 =
.52104
500
.4564 divided by .04
11.41
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