# Place value and ordering

## Presentation on theme: "Place value and ordering"— Presentation transcript:

Place value and ordering
Whole Numbers Place value and ordering Reading and writing Adding Subtracting Multiplying Dividing

Place value and ordering
The number system is made up of the digits 0,1,2,3,4,5,6,7,8,9 The position of the digit is called the place value 8 in 5834 is worth 800 8 in 4384 is worth 80

Reading and writing All numbers are split into groups of three digits from the right The first three ‘slots’ are units, tens and hundreds This pattern is repeated under the headings thousands, millions and billions

From the left work out which heading the first group is in Work out how many of these there are Continue through the number

Adding or combining Place the numbers under each other
Place the right most digit under the right most digit Place all other digits under each other

If the answer is less than 10 place underneath digits If the answer is 10 or more place unit part of answer under and carry the ‘tens’ part

Subtracting or finding difference
Write numbers similarly to adding Subtract individual columns If top number is larger then place answer underneath If top number is smaller then we must borrow

Subtracting or finding difference
BORROWING Increase top number by 10 Decrease next left number on top by one If next top left is 0 change to 9 and continue to next left

Times Tables Create your own times table X4 Double and double
X5 Hands of the clock X6 Treble then double X8 Double, double, double X9 Times 10 minus the number

Multiplying by multiples of 10,100, etc
Ignore the zeroes Multiply by the remaining number Add back in zeroes 452 x 3 = 1356 452 x 30 = 13560 4520 x 30 = 452 x 300 =

Multiplying (adding over and over) Single digits
Once you know your times tables multiplying is simple Multiply the bottom number by the individual digits If answer is less than 10 place under digit Otherwise put down ‘unit’ and carry ‘ten’ put down ‘unit’ and carry ‘ten’

Multiplying (adding over and over) Single digits
Continue multiplying through the digits of top number from right to left Put down whole answer to final multiplication

Multiplying (adding over and over) Double digits
The bottom number is broken up into units, tens, etc. Here 24 = 20 +4 First multiply by 4 Then multiply by 20 DON’T FORGET ZERO ON SECOND LINE

Division (sharing equally)
1782 divided by 6 or how many 6s make up 1782? Work through the number from left to right How many 6es go into 17? 17 divided by 6 = 2 with remainder 5 2 remainder 5

Division (sharing equally)
Move through the number How many 6es go into 58? If it doesn’t go then put a zero on top When you have run out of digits you can stop even with a remainder

Division (sharing equally)
Long division is the same as short division but we write out the multiplication to find the remainder 45 x 2 =90 carry next 9 on to 40 making 409 130 divided by 45 = 2 remainder 40

Division with remainder

Practice http://gwydir.demon.co.uk/jo/numbers/arab/index.htm