Multiplying by Powers of Ten http://hench-maths.wikispaces.com

0.5 X 100 = 50 Multiplying by Powers of 10 0.06 X 0.01 = 0.0006 Type Example Multiplying Decimals by Powers of 10 such as 10, 100, 1000 . . . Move the decimal point to the right the same number of places as there are zeros in the power of 10. 0.5 X 100 = 50 Two zeros move the .two places to the right!! Multiplying Decimals by Powers of 10 such as .1, .01, .001 . . . Move the decimal point to the left the same number of places as there are decimal places in the power of 10. 0.06 X 0.01 = 0.0006 Two decimal places move the.two places to the left!! Objective C

PLACE VALUES of the digits in this number? 5 3 7 4 8 2 What are the PLACE VALUES of the digits in this number?

5 3 7 4 8 2 So that means 500 + 30 + 7 + + +

just separates the whole numbers from the decimal fractions 5 3 7 4 8 2 The decimal point just separates the whole numbers from the decimal fractions

What happens when I multiply this number by 10 ? 5 3 7 4 8 2 What happens when I multiply this number by 10 ?

5 3 7 4 8 2 Each digits value will become 10 times bigger so the decimal moves one place to the RIGHT because there is one 0

It LOOKS like the decimal point moves one place to the RIGHT. Multiplying by 10 537.482 x 10 = 5374.82 It LOOKS like the decimal point moves one place to the RIGHT.

Multiplying by 10 Moving the digits one place to the left is the same as moving the decimal point one place to the RIGHT. 5 3 7 4 8 2 5 3 7 4 8 2

Multiplying by 100 Moving the digits two places to the left is the same as moving the decimal point two places to the RIGHT. 5 3 7 4 8 2 5 3 7 4 8 2

What happens when I multiply this number by .1? 2 9 4 1 2 5 What happens when I multiply this number by .1?

2 9 4 1 2 5 Each digits value will become 10 times smaller so the decimal moves one place to the LEFT because there is one place value

It LOOKS like the decimal point moves one place to the LEFT. Multiplying by 1 294 125 x 1 = 29 4125 It LOOKS like the decimal point moves one place to the LEFT.

Multiplying by .1 Moving the digits one place to the right is the same as moving the decimal point one place to the LEFT. 2 9 4 1 2 5 2 9 4 1 2 5

Multiplying by .01 Moving the digits two places to the right is the same as moving the decimal point two places to the LEFT. 2 9 4 1 2 5 2 9 4 1 2 5

Get white boards and markers for your group! Time to Practice!!

What do you notice about the answers? Multiply: 392 X 10 = 3,920 2) 392 X 100 = 39,200 What do you notice about the answers? 3) 392 X 1000 = 392,000 4) 4.21 X 10 = 42.1 5) 4.21 X 100 = 421 6) 4.21X 1000 = 4,210

What do you notice about the answers? Multiply: 89 X .1 = 8.9 2) 89 X .01 = .89 What do you notice about the answers? 3) 89 X .001 = .089 4) 4.21 X 10 = 42.1 5) 4.21 X 100 = 421 6) 4.21X 1000 = 4,210