The number of five-cent coins in a pouch was ¹₄ the number of twenty-cent coins. Warren took out 21 twenty-cent coins and exchanged them for five-cent coins. Then he put the money back into the pouch. The number of twenty-cent coins became ³₅ the number of five-cent coins. How much money was there in the pouch?

	Make u the same (1)x4 = (3)	5-cent (1)	20-cent (2)
Before	4 u	1 u	4 u
Change	+ 336	+ 84	- 21
After	20 p	5 p	3 p

Value of 20-cent coins to be exchanged to 5-cent coins
= 21 x 20
= 420

Number of 5-cent coins to be exchanged from the 20-cent coins
= 420 ÷ 5
= 84

(3) = (2)
20 p - 336 = 3 p + 21
20 p - 3 p = 21 + 336
17 p = 357

1 p = 357 ÷ 17 = 21

Number of 5-cent coins in the end
= 5 p
= 5 p x 21
= 105

Value of 5-cent coins in the end
= 105 x 5
= 525¢

Number of 20-cent coins in the end
= 3 p
= 3 x 21
= 63

Value of 20-cent coins in the end
= 63 x 20
= 1260¢

Total value of coins
= 525 + 1260
= 1785¢

$1 = 100¢
1785¢ = $17.85 

Answer(s): $17.85