Maths: more fractions

HideShow resource information

Common denominators

When a question asks you to put some fractions in ascending order of size all you have to do is find the lowest common multiple in the denominators of the fractions and times the original numerator and denominator by the number needed to get to that common multiple.

1) 8/3 5/4 12/5 the lowest common multiple between these fractions is 60.
2) now we have to times the numerator and the denominators of the fractions to get to that LCM so 8/3 X 20= 160/60 5/4 X 15 = 75/60 12/5 X 12 = 144/60.
3) now remember to put the numbers from smallest to biggest if the question asks so so it'd be 5/4, 12/5 and 8/3

1 of 3

Adding and subtracting fractions

1) make sure the denominators of the two fractions are the same.
2) If the fractions are mixed numbers convert them to inproper fractions.
3) Add or subtract the top lines only!

Practise question:
Calculate 2 1/5 - 1 1/2
11/5 - 3/2
11/5 X 2 = 22/10 3/2 X 5 = 15/10
22/10 - 15/10 = 7/10

2 of 3

Finding a fraction of a whole number

1) divide by the denominator.
2) Times by the numerator.

Practise question what is 9/20 of £360
360 divided by 20 = 18
18 X 9 = 162

3 of 3

Comments

No comments have yet been made

Similar Mathematics resources:

See all Mathematics resources »See all Fractions, decimals and percentages resources »