1-1

Decimal place-value chartH

undr

eds

Tho

usan

ds

Ten

s

One

s

Hun

dred

ths

Ten

ths

Ten

Tho

usan

dths

Tho

usan

dths

Hu

nd

red

Th

ousa

nd

ths

1,000 100 10 1 110

1 . 100

1 . 1,000

1 . 10,000

1 . 100,000

Dec

imal

Poi

nt

and

1-2

Rounding Decimals

.3272727

.337272

Step 1. Identify the place value of the digit you wantto round

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

Step 3. Drop all digits to the right of the identified digit

.33

1-3

Converting Proper Fractions to Decimals

34

4 3.00

2.8

20

20

0

.75

EQUALS

.75

1-4

Converting Pure Decimals to Decimal Fractions

24 1

24

24100

2

.24

Step 1

Step 2

Step 3

Places

1-5

Adding and Subtracting Decimals

Add: 7 + 5.3 + 24.139 + .0003 + 5.02

7.0000

5.3000

24.1390

.0003

5.0200

41.4593

1-6

Multiplying Decimals

6.91x .025

34542 34.5423 decimal places

17275 .172755 decimal places

9.09x 3.8

1-7

Dividing Decimals3 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.

4.5 82.89

45. 828.9

45. 828.90 45 378 360 189 180 90 90

18.42

Answer

Question

1-8

Shortcuts for Multiples of 10

6.89 x 10

6.89 x 100

6.89 x 1000 68.96890

689

•Count the zeros in the multiplier

•Move the decimal point the same

number of spaces to the right

MultiplicationMultiplication

1-9

Shortcuts for Multiples of 10

6.89 / 10

6.89 / 100

6.89 / 1000 .689.00689

.0689

•Count the zeros in the divisor

•Move the decimal point the same

number of spaces to the right

DivisionDivision

1-10

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