Albert and Seth had 76 marbles in total. Albert had 12 marbles less than Seth at first. After Albert and Seth played a game with Jean, Albert had ³₅ as many marbles as Seth. If Albert lost as many marbles as Seth to Jean, find the number of marbles that Seth lost to Jean.

	Albert	Seth	Difference
Before	1 u	1 u + 12	12
Change	- ?	- ?
After	3 p	5 p	2 p

Total number of marbles at first
= 1 u + 1 u + 12 
= 2 u + 12

2 u + 12 = 76
2 u = 76 - 12
2 u = 64

1 u = 64 ÷ 2 = 32

Since Albert lost the same number of marbles as Seth, the difference in the number of marbles between Albert and Seth at first and in the end remains the same.

Difference in the number of marbles in the end
= 5 p - 3 p
= 2 p

2 p = 12

1 p = 12 ÷ 2 = 6

Number of marbles that Albert lost to Jean
= 1 u - 3 p
= 32 - 3 x 6
= 32 - 18
= 14

Since Seth lost the same number of marbles as Albert, the number of marbles that each lost to Jean is the same.

Number of marbles that Seth lost = 14

Answer(s): 14