Question

If z varies directly as y and inversely as the square root of x, by how much should x be increased so that z is kept constant when y is increased by 15%? If z varies directly as y and inversely as the square root of x, by how much should x be increased so that z is kept constant when y is increased by 15%?

Answer 1

32.25%

Explanation:

The equation of variation is z = ky/√x

When y is increased by 15%, we have value of y = 1.15y.

To keep z constant √x must = 1.15 so x must be 1.15^2 = 1.3225.

Therefore x must be increased by 0.3225 or 32.25%.