UNIT 1 Multiply and divide any positive integer up to 10 000 by 10 or 100 and understand the effect.

Decimals Multiply & Divide by 10, 100, 1000 Learning Intention Level E Learning Intention Success Criteria 1. To understand how to multiply and divide decimal numbers by 10, 100, 1000. Understand the simple rules to multiply and divide decimal numbers. 2. Be able do calculations. 3. To understand the effect. Sunday, 30 August 2009 DiscoveringTime

The effect of multiplying a number by 10, 100, 1000 & 10000 ten thousands thousands hundreds tens units 6x1 6 six 6x10 6 sixty 6 6x100 six hundred 6x1000 6 six thousand 6x10000 6 sixty thousand What is happening ?

The effect of dividing a number by 10, 100, 1000 & 10000 Decimal points units tenths hundredths thousandths Level E 7 1 7 seven 7 10 7 nought point seven 7 100 7 nought point nought seven 7 1000 7 nought point nought nought seven What is happening ?

Level E Multiplying a whole number by 10 Example 2 4 6 x 1 thousands hundreds tens units 2 4 x 10 6 2 4 6 add place holder zero to the units column = 246 x 10 = 2460 all digits move one place to the left

Level E Multiplying a decimal by 100 Example 6 2 9 4 x 1 tenths ten thousands thousands hundreds tens units Decimal point 6 2 x 100 9 4 6 2 9 4 = add place holder zeros to the units columns 629.4 x 100 = 62940 all digits move two places to the left

Decimals Multiply & Divide by 10, 100, 1000 Level E To multiply a decimal number by 10, Simply move all digits 1 place to the left: e.g. 2.55 x 10 = 25.5 digits are moved 1 place to left To multiply a decimal number by 100, Simply move all digits 2 places to the left: e.g. 1.02 x 100 = 102.0 digits are moved 2 places to left DiscoveringTime Sunday, 30 August 2009

Decimals Multiply & Divide by 10, 100, 1000 Level E To multiply a decimal number by 1000, Simply move all digits 3 places to the left: e.g. 34.567 x 1000 = 34 567 digits are moved 3 places to left DiscoveringTime Sunday, 30 August 2009

Level E Multiplying a whole number by 100 Example 9 3 5 x 1 ten thousands thousands hundreds tens units 9 3 x 100 5 9 3 5 add place holder zeros to the units & tens columns = 935 x 100 = 93500 all digits move two places to the left

Level E Multiplying a decimal by 100 Example 4 3 1 7 x 1 tenths ten thousands thousands hundreds tens units Decimal point 4 3 x 100 1 7 4 3 1 7 = add place holder zeros to the units columns 431.7 x 100 = 43170 all digits move two places to the left

Level E Dividing a whole number by 10 Example 786 10 hundreds tens units Decimal point tenths 7 8 10 6 6 7 8 = 786 10 = 78.6 all digits move one place to the right

Level E Dividing a whole number by 100 Example 786 100 hundreds tens units Decimal point tenths hundredths 7 8 100 6 7 8 6 = 786 100 = 7.86 all digits move two places to the right

As the following numbers appear multiply them by 10. 1.92 0.638 6.75 12.82 1.4 As the numbers appear multiply by 100. 0.67 16.8 2.5 8.324 1.56

Level E Plenary Sunday, 30 August 2009