We don't know how many of ANY color are in the bag right now, so there's no way to calculate an answer.
What Tom has to do is make sure that the number of marbles that are NOT blue is NINE TIMES the number of blue ones in the bag.
We use the equation y = kx
y = 18, x = 2.5
18 = k2.5
k = 7.2
x = 6.4
y = 7.2*6.4
y = 46.08
hope this help
