If the product of two positive numbers be 1575 and their ration is 7 : 9, then the greatest number is :

A. 45

B. 135

C. 35

D. 63

Answer: Option A

Solution(By Examveda Team)

Let the numbers are 7x and 9x
According to the question,
$$\eqalign{ & \Rightarrow 7x \times 9x = 1575 \cr & \Rightarrow 63{x^2} = 1575 \cr & \Rightarrow {x^2} = 25 \cr & \Rightarrow x = 5 \cr} $$
Then greater number
= 9x
= 9 × 5
= 45