312g

1 tiers = 1/3        et 1/3 x 312 = 104g

2 tiers = 2/3      et 312 x 2/3 = 208 g

3 quarts = 3/4       et 312x 3/4 = 234 g

1/2 = 1/2            et 312 x 1/2 = ..... g