Question

Assume that y varies directly with x . Ify = 18when x = 6 , findywhen x = 5 . Write and solve a direct variation equation to find the answer. y =

Answer 1

y = 15

Explanation:

It's given in this question that y varies directly with x.

That means, y ∝ x

⇒ y = kx (where k is the proportionality constant)

If y = 18 when x = 6,

⇒ 18 = 6k

⇒ k = 3

Therefore, relation between x and y is,

y = 3x

From this relation, if x = 5

y = 3×5

y = 15

Therefore, for x = 15 value of y will be 15.