Question

Suppose c and d vary inversely, and d = 2 when c = 17.

a. write an equation that models the variation?
b. find d when c = 68

Answer 1

c = 34/d

d = 1/2

Explanation:

Part A

Basic Formula

c = k/d

17 = k/2 Multiply both sides by 2

17*2 = k*2/2 Combine

34 = k

So the equation is c = 34/d

Part B

c = 68

k = 34

d = ?

68 = 34/d Multiply both sides by d

68*d = 34 * d/d Simplify.

68 d = 34 Divide by 68

d = 34/68 Simplify

d = 1/2