Page 50 - TB_5B
P. 50
Objective: Learn how to multiply decimals
The placement of a decimal point in multiplication.
If you multiply a decimal by 10, 100, or 1,000, the decimal point moves to the
right according to the number of zeros.
$1.71 1 = $1.71 42.43 1 = 42.43
$1.71 10 = $17.1 42.43 10 = 424.3
$1.71 100 = $171 42.43 100 = 4243
$1.71 1,000 = $1710 42.43 1,000 = 42430
Learn how to use fractions to multiply decimals.
Multiply. 1.23 1,000
1.23 10 = 123 10 = 1,230 = 12.3
100 100
1.23 100 = 100 100 = 100 0.1 = 1 0.01 = 1
= 10 100
1.23 1,000 = 100 1,000 = 100 Decimals can be
=
expressed as fractions
Multiply. 0.008 6
with the denominator of
10 or 100.
0.5 = 5 2.34 = 234
10 100
0.8 6 = 10 6 = 10 = Fractions with 10 or 100
as the denominator can
be expressed as decimals.
0.08 6 = 100 6 = 100 = 3 = 0.3 120 = 1.2
10 100
0.008 6 = 1000 6 = 1000 =
21. Multiplying by Decimals 39
The placement of a decimal point in multiplication.
If you multiply a decimal by 10, 100, or 1,000, the decimal point moves to the
right according to the number of zeros.
$1.71 1 = $1.71 42.43 1 = 42.43
$1.71 10 = $17.1 42.43 10 = 424.3
$1.71 100 = $171 42.43 100 = 4243
$1.71 1,000 = $1710 42.43 1,000 = 42430
Learn how to use fractions to multiply decimals.
Multiply. 1.23 1,000
1.23 10 = 123 10 = 1,230 = 12.3
100 100
1.23 100 = 100 100 = 100 0.1 = 1 0.01 = 1
= 10 100
1.23 1,000 = 100 1,000 = 100 Decimals can be
=
expressed as fractions
Multiply. 0.008 6
with the denominator of
10 or 100.
0.5 = 5 2.34 = 234
10 100
0.8 6 = 10 6 = 10 = Fractions with 10 or 100
as the denominator can
be expressed as decimals.
0.08 6 = 100 6 = 100 = 3 = 0.3 120 = 1.2
10 100
0.008 6 = 1000 6 = 1000 =
21. Multiplying by Decimals 39
