The number of five-cent coins in a bag was ¹₃ the number of twenty-cent coins. Bobby took out 24 twenty-cent coins and exchanged them for five-cent coins. Then he put the money back into the bag. The number of twenty-cent coins became ³₅ the number of five-cent coins. How much money was there in the bag?

	Make u the same (1)x3 = (3)	5-cent (1)	20-cent (2)
Before	3 u	1 u	3 u
Change	+ 288	+ 96	- 24
After	15 p	5 p	3 p

Value of 20-cent coins to be exchanged to 5-cent coins
= 24 x 20
= 480

Number of 5-cent coins to be exchanged from the 20-cent coins
= 480 ÷ 5
= 96

(3) = (2)
15 p - 288 = 3 p + 24
15 p - 3 p = 24 + 288
12 p = 312

1 p = 312 ÷ 12 = 26

Number of 5-cent coins in the end
= 5 p
= 5 p x 26
= 130

Value of 5-cent coins in the end
= 130 x 5
= 650¢

Number of 20-cent coins in the end
= 3 p
= 3 x 26
= 78

Value of 20-cent coins in the end
= 78 x 20
= 1560¢

Total value of coins
= 650 + 1560
= 2210¢

$1 = 100¢
2210¢ = $22.10 

Answer(s): $22.10