Three cartons, B, C and A, contained 235 marbles. Pierre added some marbles into Carton B and the number of marbles in Carton B tripled. He took out half of the number of marbles from Carton C and removed 48 marbles from Carton A. As a result, the ratio of the number of marbles in Carton B, Carton C and Carton A became 12 : 3 : 7. What was the ratio of the number of marbles in Carton A to the total number of marbles in Carton B and Carton C at first? Give the answer in its lowest term.

	Carton B	Carton C	Carton A	Total
Before	1x4 = 4 u	2x3 = 6 u	7 u + 48	235
Change	+ 2x4 = + 8 u	- 1x3 = - 3 u	- 48
After	3x4 = 12 u	1x3 = 3 u
Comparing the 3 cartons	12 u	3 u	7 u

The number of marbles in Carton B in the end is the same. Make the number of marbles in Carton B in the end the same. LCM of 3 and 12 is 12.

The number of marbles in Carton C in the end is the same. Make the number of marbles in Carton C in the end the same. LCM of 1 and 3 is 3.

Total number of marbles at first
= 4 u + 6 u + 7 u + 48
= 17 u + 48

17 u + 48 = 235
17 u = 235 - 48
17 u = 187

1 u = 187 ÷ 17 = 11

Number of marbles in Carton A at first
= 7 u + 48
= 7 x 11 + 48
= 77 + 48
= 125

Number of marbles in Carton B and Carton C at first
= 235 - 125
= 110

Carton A : Carton B and Carton C
125 : 110 _(÷5)
25 : 22

Answer(s): 25 : 22