We run a business that rents out canoes and kayaks. A canoe rental costs $12 per day, and a kayak rental costs $18 dollars per day. One day, our business rents out 3 canoes for every 2 kayaks and receives a total of $504 in revenue. How many more canoes than kayaks were rented out?  Choose one:
A) 5
B) 6
C) 7
D) 8
E) 9
Let x be the number of canoes.   Then 2x/3 is the number of kayaks.   12x+(2x/3)*18=504   12x+12x=504   24x=504   x=21 (canoes)   2x/3=14 (kayaks)   There were   21-14= 
<gadget id="calculator">  21-14</gadget>
<output>7</output>
7 more canoes rented out.   The answer is 7.
<result>C</result>
We run a business that rents out canoes and kayaks. A canoe rental costs $12 per day, and a kayak rental costs $18 dollars per day. One day, our business rents out 3 canoes for every 2 kayaks and receives a total of $504 in revenue. How many more canoes than kayaks were rented out?