Question

Sam delivers 3 newspapers in 5 minutes. If he continues at this rate, how long will it take him to deliver 45 newspapers?

Answer 1

It will take him 75 minutes.

Explanation:

Rule of three / cross-multiplication:

3 newspapers require 5 min

45 newspapers require x min

x = (45 / 3) * 5

x = 15 * 5

x = 75 min

Answer 2

75 minutes

Explanation:

3 newspapers = 5 minutes

45 newspapers = x minutes

45/3 = 15

3 x 15= 45 newspapers

5 x 15 = 75 minutes

Another way:

x= minutes

45/3= x/5

15=x/5

75=x