A bag contains hundreds of glass marbles, each one coloured either red, orange, green or blue. There are more than 2 marbles of each colour. Marbles are drawn randomly from the bag, one at a time, and not replaced.
How many marbles must be drawn from the bag in order to ensure at least three marbles of the same colour are drawn?
Select one option, then click Submit.
4
7
9
12
13
Select an option, then submit.
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