Joint and Combined Variation Answers

The quantity y varies directly as x and inversely as z. When x is 10 and z is 4, y is 15. What is y when x is 20 and z is 6?

A quantity m varies jointly with p and r. When p is 2 and r is 4, m is 1. What is the constant of variation?

The amount of time it takes p people to paint d doors varies directly with the number of doors and inversely with the number of people. Four people can paint 10 doors in 2 hours. How many people will it take to paint 25 doors in 5 hours?

A quantity b varies jointly with c and d and inversely with f. When c is 4, d is 9, and f is 6, b is 18. What is the constant of variation?

A quantity x varies directly with y and inversely with z. Which expression represents the constant of variation, k?

The quantity y varies directly with the square of x and inversely with z. When x is 9 and z is 27, y is 6. What is the constant of variation?

It takes 4 lawnmowers to cut 2 acres of grass in 2 hours. If the amount of time varies directly with the amount of grass and inversely with the number of lawnmowers, how many hours will it take 2 lawnmowers to cut 6 acres of grass?

When f = 2 and g = 8, n = 4. If n varies jointly with f and g, what is the constant of variation?

A quantity p varies jointly with r and s. Which expression represents the constant of variation, k?

A quantity h varies directly with w and inversely with p. When w = 4 and p = 6, h = 2. What is the constant of variation?