Fractions Simplifying Equivalences Equivalent Fractions of one half

Fractions • Simplifying • Equivalences

Equivalent Fractions of one half The bottom number is twice the top number The top number is half the bottom number

In a fraction the top number is the numerator. The bottom number is the denominator. Which of these fractions are equivalent to a half. Look at the relationship between the numerator and the denominator. 8 x 2=16 so no It is relatively easy to see ifsoa yes 11 x 2=22 fraction equals a half or not. 15 x 2= 30 so yes

Which of these are equivalent to a third? Is the bottom number three times the top number? No Yes Yes No Yes

Simplifying fractions – a general method You have to find a common divisor – a number which will go into both the top number and the bottom number and leave no remainder

Find a number that will go into the numerator and denominator and leave no remainder What number will go into 25 and 100 and leave no remainder? 5 is a possibility What number will go into 5 and 20 and leave no remainder? 5 is a possibility again We can’t go any further

Find a number that will go into the numerator and denominator and leave no remainder What number will go into 28 and 42 and leave no remainder? They are both even numbers so two will work What number will go into 14 and 21 and leave no remainder? 7 will We can’t go any further

Simplifying fractions- You need to know your times tables Even numbers end in 0, 2, 4, 6, 8 – Two will always go into and even number. Here are some even numbers 32 74 18 96 110

Simplifying fractions- You need to know your times tables To see if 3 goes into a number – see if three goes into the sum of the digits – example - 39 (3+9=12=3 x 4) Here are some numbers that are divisible by three 51 5+1=6=3 x 2 63 6+3=9=3 x 3 108 48 1+0+8=9=3 x 3 4+8=12=3 x 4

Simplifying fractions- You need to know your times tables Five will go into any number that ends in zero or five Ten will go into any number that ends in zero Twenty five will go into any number that ends in 00, 25, 50, 75

Try to simplify these fractions