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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