1. Decimal place-value chart
Decimal Point
Hundredths
Ten Thousandths
Thousands
Hundreds
Tens
Ones
Tenths
Thousandths
Hundred Thousandths
1,000
100 10 1
and 1 10
1 .
100
1 .
1,000
10,000
100,000

2. Rounding Decimals .33 .3272727 .337272 Step 1. Identify the place
value of the digit you want
to round
Step 3. Drop all digits to the right of the identified digit
Step 2. Identify the digit to the right.
If 5 or more, increase the identified digit
by 1. If less than 5 do not change
.33

3. Converting Proper Fractions to Decimals
.75
2.8 20
EQUALS 3 4
.75

4. Converting Pure Decimals to Decimal Fractions
Step 1 24
Step 2 24 1
.24
Places 2
Step 3 24
100

5. Adding and Subtracting Decimals
7.0000
5.3000
.0003
5.0200

6. Multiplying Decimals 9.09 x 3.8 3 decimal places 34542 34.542
17275
.17275
6.91 x

7. Dividing Decimals 3 Steps
Make the divisor a whole number by moving the decimal point to the right
Move the decimal point in the dividend to the right the same number of places as in step 1. If there are not enough places, add zeros to the right of the dividend.
Place the decimal point in the quotient above the new decimal point in the dividend. Divide as usual.
Question
Answer
18.42 45
378
360
189
180 90

8. Shortcuts for Multiples of 10
Multiplication
Count the zeros in the multiplier
Move the decimal point the same
number of spaces to the right
6890
68.9
6.89 x 1000
6.89 x 10
6.89 x 100
689

9. Shortcuts for Multiples of 10
Division
Count the zeros in the divisor
Move the decimal point the same
number of spaces to the right
.00689
.689
6.89 / 1000
6.89 / 10
6.89 / 100
.0689

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