Ratio

Ratio examples:

Ratio is the numerical relation of one quantity to another of the same kind. To find the ratio of 2 m 25 cm to 75 cm, they first change 2 m 25 cm in to cm, which equals 225 cm. Now, they must find 225 cm to 75 cm
ratio is
= 3 : 1
They can write the above ratio as
(i) 3 : 1 or (ii) or (iii) the ratio 3 to 1 or (iv) 3

More help on:
Mean and standard deviation

Variance formula