@jheyenmeye: ben gave brian 3/4 of piece marbles. brian gave bob 3/4 of the marbleshe got from ben. bob gave basti 3/4 of the marbles he got from brian. basti got only 8 marbles. how many did ben start with?
I can explain the answer to you, but since it doesn't give a round number as answer, I think you might have written down something wrong in your question.
Suppose you would know the amount ben started with instead of the amound basti ended up with (lets take 64 for example). Then to calculate the amount basti ended with you would multiply this amount (so for the example 64) first by 3/4, then again by 3/4 and then again by 3/4 like this; 64 * (3/4) * (3/4) * (3/4) = 27.
To go the other way we simply need to divide instead of multiply so;
8/(3/4)/(3/4)/(3/4) = 512/27 or similarly 18 26/27th or aprox. 18.96 marble
Reinout
+2353 
