Answer:
36
Step-by-step explanation:
There are 30 red marbles and the ratio of black to yellow is 4/5, so 4/5=orange/green=orange/30.
30 is 6 times 5, so black=6 times 4=24. There are 24 black marbles.
Total of black and yellow=24+30=54.
40% of the marbles are green so 60% are black/yellow. Also 60% is 54 marbles.
60% is 60/100=3/5 so 3/5 of the total is 54 marbles, therefore 1/5 is 54/3=18 and 2/5 is the number of red marbles=2 times 18=36 red marbles.
to be honest i can't think of anything original for the visual thing, but i think the pi chart from the person above me would work well
