green marbles --- x
blue marbles --- 2x
red marbles ---- 3(2x) = 6x
x + 2x + 6x = 765
...
..
carry on.
there are 765 marbles in a in a box. there are twice as many blue marbles as green marbles. there are 3 times as many red marbles as blue marbles, how many red marbles in the box
2 answers
85