Question

Suppose that 13 inches of wire costs 78 cents.

At the same rate, how much (in cents) will 7 inches of wire cost?

Answer 1

$0.42

Explanation:

create a proportion:

13/.78 = 7/x

cross-multiply to get:

13x = 7(.78)

13x = 5.46

x = 5.46/13

x = .42