Reggie saved some 10-cent coins and $2 notes in his coin box. The total value of the 10-cent coins to the total value of the $2 notes he had was in the ratio 1 : 5. After $25 worth of 10-cent coins and an equal value of $2 notes were added to the coin box, the ratio of the total value of 10-cent coins to the total value of $2 notes became 3 : 5. How many of each type did Reggie have in the end?

1. 10-cent coins?
2. $2 notes?

	Value of 10-cent	Value of $2	Difference in  value
Before	1x1 = 1 u	5x1 = 5 u	4x1 = 4 u
Change	+ 25	+ 25
After	3x2 = 6 u	5x2 = 10 u	2x2 =  4 u

(a)
The difference in values between 10-cent and $2 remains unchanged. Make the difference in value the same. LCM of 4 and 2 is 4.

Increase in the value of 10-cent coins after more were added
= 6 u - 1 u
= 5 u

5 u = 25

1 u = 25 ÷ 5 = 5

Value of 10-cent coins in the end
= 6 u
= 6 x 5
= $30

100¢ = $1
10¢ = $0.10 

Number of 10-cent coins in the end
= 30 ÷ 0.10
= 300

(b)
Value of $2 notes in the end
= 10 u
= 10 x 5
= $50

Number of $2 notes in the end
= 50 ÷ 2
= 25

Answer(s): (a) 300; (b) 25