⁵₇ of Glen's savings comprised of 20-cent coins and 50-cent coins. Glen used some 20-cent coins to purchase a flying saucer. The number of 50-cent coins left was 40% more than the number of 20-cent coins left. Given that Glen had 36 more 50-cent coins than 20-cent coins left in the end, find the amount of money Glen spent on the flying saucer.

	20-cent coins	50-cent coins
Before	5x7 = 35 u	2x7 = 14 u
Change	- 25 u
After	5x2 = 10 u	7x2 = 14 u

Fraction of Glen's savings that comprised of 50-cent coins
= 1 - ⁵₇
= ²₇

Number of 50-cents coins in the end in percentage
= 100% + 40%
= 140%

140% = ¹⁴⁰₁₀₀ = ⁷₅

Number of 50-cent coins remains unchanged. Make the number of 50-cent coins the same.  LCM of 2 and 7 is 14.

Number of more 50-cent coins than 20-cent coins
= 14 u - 10 u
= 4 u

4 u = 36

1 u = 36 ÷ 4 = 9

Number of 20-cent coins spent on the flying saucer 
= 35 u - 10 u
= 25 u
= 25 x 9
= 225

Amount that Glen spent on the flying saucer 
= 225 x 0.2
= $45

Answer(s): $45