At the office supply store, a box of 25 pens cost $7.19, a box of 50 pens cost $10.78, a box of 75 pens cost $14.50 and a box of the 125 cost $26.25. Which box has the cheapest pen per cost?

Answer 1

To get the cost per pen: Total cost/# of pens

$7.19/25 = $.29

$10.78/50 = $.22

$14.50/75 = $.19

$26.25/125 = $.21

The cheapest is $14.50/75 = $.19

Answer 2

7.19/25 = 0.2876

I bet you can get the rest!