place value and multiplication

Place Value and Multiplication

millions thousands

100 10 1 100 10 1 100 10 1Before the

decimal point . After the decimal point

1000 100 10 1 . 1/101/100

1/10001/10000

Place Value & X by 10

millions thousands

100 10 1 100 10 1 100 10 1

3 2

7, 8 9 5

3 2 0

7 8, 9 5 0

Place Value & X by 10

millions thousands

100 10 1 100 10 1 100 10 1

2 3, 4 5 6

8 9, 0 1 2, 3 4 5

2 3 4, 5 6 0

8 9 0, 1 2 3, 4 5 0

Place Value & X by 10

thousands After the decimal point

100 10 1 100 10 1 . 1/10 1/100

0 . 8 2

1 . 0 3

8 . 2

1 0 . 3

When you multiply by ten

• The answer gets bigger

• The decimal point moves to the right one place or the numbers move one place to the left

4 6 . 5 9. 2 3 . 0

2 3 0 .

Multiply by 10 -

0.06 x 10 0.06 x 10 ==

4.209 x 10 4.209 x 10 ==

3.52 x 10 =3.52 x 10 =

0.0086 x 10 0.0086 x 10 ==

35.235.2

42.0942.09

0.60.6

0.0860.086

The answer gets bigger

Place Value & X by 100

millions thousands

100 10 1 100 10 1 100 10 1

3 2

7, 8 9 5

3, 2 0 0

7 8 9, 5 0 0

Place Value & X by 100

millions thousands

100 10 1 100 10 1 100 10 1

3, 4 5 6

9, 0 1 2, 3 4 5

3 4 5, 6 0 0

9 0 1, 2 3 4, 5 0 0

When you multiply by a hundred

• The answer gets bigger

• The decimal point moves to the right two places or the numbers move two places to the left

4 6 . 5 9 . 3 2 . 8

22 88 0

Multiply by 100• 6 x 100

• 12 x 100

• 25 x 100

• 64 x 1000.16 x 0.16 x 100100

4.23 x 1004.23 x 100

13.5 x 13.5 x 100100

0.063 x 0.063 x 100100

= 1200

= 600

= 2500

= 6400 = 6.3

= 1350

= 423

= 16

When you multiply by a thousand

• The answer gets bigger

• The decimal point moves to the right three places or the numbers move three places to the left

4 6. 5 9 . 32 . 3 5

222 333 555 0

Multiply by 1000 • 6 x 1000

• 12 x 1000

• 25 x 1000

• 64 x 10000.16 x 0.16 x 10001000

4.23 x 4.23 x 10001000

13.5 x 13.5 x 10001000

0.063 x 0.063 x 10001000

= 12,000

= 6,000

= 25,000

= 64,000 = 63

= 13,500

= 4,230= 160

When multiplying by 10,100,1000-• I know that the number gets bigger

• The place value of each digit is changing

or

the decimal point is moving

Can I do this multiply by just looking at it?101011 =10 =10 101022 =10 x 10 =100 =10 x 10 =100101033 =10 x 10 x 10 =1000 =10 x 10 x 10 =1000101044 = 10 x 10 x 10 x 10=10000 = 10 x 10 x 10 x 10=10000