Question

If weight of 5 books is 2.5 kg then 30 kg will be weight of how many books?

Answer 1

Let 30 kg be the weight of x books.

Here direct relation occurred.

5 : x :: 2.5 x 30

Product of outer terms = Product of middle terms

⇒ 5 × 30 = x × 2.5

⇒ x = (5 x 30)/2.5

⇒ x = 60

Hence, 60 books having 30 kg. weight.