Question

If X varies directly as Y and if X = 7 when Y=28 , Find X when Y is 84?​

Answer 1

Answer :

• x is 21

Given :

• If x varies directly as y and if x = 7 when y = 28

To find:

• Find x when y is 84

Solution :

Given that,

• x varies directly as y so,

We know that

• x = ky

Given that,

• x = 7
• y = 28

First we need to find the k

↝ x = ky

↝ 7 = k(28)

↝ 7 = 28k

↝ k = 7/28

↝ k = 1/4

Now, Finding the x when y is 84 so,

Given,

• y is 84

↝ x = ky

↝ x = 1/4 × 84

↝ x = 21

Hence , x is 21.