Question

The variables x and y vary inversely, when x is 9 y is 36 if x is 3 what is y?

Answer 1

According to the question,

x1/X2 = y2/y1

3/9 = 36/y

3y = 36 * 9

y = 108.

Hope it helps ;-)

Answer 2

According to the question,

x ∝ 1/y

Or, xy = k (where, k is a non zero variation constant)

Now, 9 × 36 = k

Or, 324 = k

Now, secondly, we can say :

xy = k

Or, 3 × y = 324 (putting values each)

Or, y = 324/3 = 108 [ANSWER]