5 balls are picked at random one at a time and then replaced. If 65% of balls are blue, 30% are red and 5% are green. Then what is the probability that
i) All 5 balls are red
ii) 3 are blue, 1 is green and 1 is red
iii) At least 1 is a green
To the OP: Read Multinomial distribution - Wikipedia, the free encyclopedia
The reason it has to be multiplied is exactly because order does not matter.
Assumes that you first pick three blue balls, then a green one, then a red one. Because order does not matter, you'll need to multiply this by the amount of combinations possible, which in this case is: