Work out 2/3 - 1/4
numerator/denominator
First we need to find the common denominator (a number that can be divided by both 3 and 4)
3 x 4 = 12 (so our new, common, denominator is 12)
Whatever we do to the bottom of a fraction (the denominator) we must also do to the top
For 2/3 we multiplied 3 (the denominator) x 4 to get the new common denominator (12) and so we also need to multiply the numerator (2) by 4
2/3 = 8/12
For 1/4 we multiplied 4 (the denominator) x 3 to get the new common denominator (12) and so we also need to multiply the numerator (1) by 3
1/4 = 3/12
So our new problem is 8/12 - 3/12
Working across the numerators we do our subtraction problem, but the denominator will remain the same
8/12 - 3/12 = 5/12 (this is the final answer as this fraction cannot be simplified any further)
Related Maths KS3 answers
All answers ▸There are 12 counters in a bag. 1/2 are red, 1/3 of the remaining counters are blue. The rest are green. How many counters are green?
The maximum capacity of a glass box is 1900cm^3. A cylindrical cup of radius 4cm and height 10cm is filled to the top with water. The water is then poured into the rectangular container. How many full cups are needed to fill the box with water completely?
Expand and simplify: 4(2x − 3) − 2(x − 5)
Simplify fully (3x^2-8x-3)/(2x^2-6x)