Pencils and cents
If p perncils cost c cents how many pencils can be purchased for d dollars?
Think of this in terms of units; we need to convert d dollars into pencils. Now, we know how to convert cents to pencils: c cents = p pencils. So:
Originally Posted by Godfather
d dollars x (100 cents/1 dollar) x (p pencils/c cents) = 100dp/c pencils.