Pick up the original question-how many copies did Class One, Class Two and Class Three donate?

Take class one as 1, class two as 3/4 and class three as 7/6.

The proportion of the three types is1:3/4: 7/6 =12: 9:14.

385÷( 12+9+ 14)= 1 1

So Class One donated1/kloc-0 /×12 =132 copies.

Class two donated 1 1× 9 = 99 copies.

Three shifts of donations1/kloc-0 /×14 =154 copies.