Question no.4 From ML aggarwal book, class10, chapter 7, ratio and proportion

In this question we have been given that If (pa + qb) : (pc + qd) :: (pa – qb) : (pc – qd) and we have to apply mathematical operations to prove that a : b : : c : d

Question no 4, 7.3

Solution:It is given that

(pa + qb): (pc + qd) :: (pa – qb): (pc – qd)

We can write it as

Therefore, it is proved that a: b :: c: d.