If 17: 15 ∷ 51:x, then find the value of x.

A 51

B 45

C 3

D 17

E None of these

Correct Answer: Option B

Formula:

If four terms are in proportion, then product of means = Product of extremes

As, If a:b∷c:d,

then (b × c) = (a × d)

Now, 17:15∷51:x

So 15 × 51 = 17 × x

⇒ x = 45