Question

If a bag has 40 red and blue marbles and a quarter of them are red what is the probability of picking a blue one

Answer 1

Total marbles = 40 & 1/4  (or 0.25) are, then RED = 40x 0.25 = 10

If RED = 10 then BLUE = 30

P(picking one blue) = 30/40 = 3/4 =0.75