The number of Eric's $5 notes to $10 notes was 3:2 at first. He used 1/5 of his $10 notes and some $5 notes to pay for a gift. The ratio of the number of $5 notes to $10 notes spent on the gift was 3:1. If the amount of $5 notes left was $360, how much did the gift cost?
Let the number of $5 notes ==F
Let the number of $10 notes ==T
5F/(10T) == 3/2................. .......(1)
1/5T + G ==Cost of the Gift.
G / (1/5T) ==3/1.........................(2)
5F - 5G ==360...............................(3), solve for F, T, G
F==90 - $5 bills, T==30 - $10 bills, G==18 - $5 bills spent on Gift.
(1/5 x (30 x 10) + (18 x 5) ==$60 + $90==$150 - Cost of the Gift.
