⁴₉ of Simon's savings comprised of 10-cent coins and 50-cent coins. Simon used some 10-cent coins to purchase a flying saucer. The number of 50-cent coins left was 50% more than the number of 10-cent coins left. Given that Simon had 50 more 50-cent coins than 10-cent coins left in the end, find the amount of money Simon spent on the flying saucer.

	10-cent coins	50-cent coins
Before	4x3 = 12 u	5x3 = 15 u
Change	- 2 u
After	2x5 = 10 u	3x5 = 15 u

Fraction of Simon's savings that comprised of 50-cent coins
= 1 - ⁴₉
= ⁵₉

Number of 50-cents coins in the end in percentage
= 100% + 50%
= 150%

150% = ¹⁵⁰₁₀₀ = ³₂

Number of 50-cent coins remains unchanged. Make the number of 50-cent coins the same.  LCM of 5 and 3 is 15.

Number of more 50-cent coins than 10-cent coins
= 15 u - 10 u
= 5 u

5 u = 50

1 u = 50 ÷ 5 = 10

Number of 10-cent coins spent on the flying saucer 
= 12 u - 10 u
= 2 u
= 2 x 10
= 20

Amount that Simon spent on the flying saucer 
= 20 x 0.1
= $2

Answer(s): $2