There were some marbles in a box for sale. Leon bought 3/4 of all the marbles in
the box and he was given 8 marbles free. Next, Hariz bought 1/2 of the remaining
marbles and he was given 4 marbles free. Later, Jackson bought 1/3 of the
remaining marbles and he was given 2 marbles free. At the end, there were 10
marbles left in the box.
How many marbles were there at first?
