The ratio of the number of yellow circles to the number of white circles is 1 : 4. For each yellow circle there are 4 white circles. The ratio 3 : 12 is equivalent to 1 : 4 because for each yellow ...

Sometimes you can divide the top and bottom of a fraction by the same number. This is called cancelling down. It is also called simplifying the fraction. You often have to write a fraction in its ...