In a bottle of 3 red, 4 green and 5 blue marbles, if 2 marbles are taken out, what is the probability that two marbles are of red color
my answer is 1/4 i just did like number of red balls by total number balls .
i have another confusion like 3c2/12c2 which is 1/22...which is correct
There are a total of marbles in the bag, 3 of these are red.
Taking out one marble means there is a chance that it is red. Also there are now only 11 marbles in the bag
The chance that this is also red is because there are only 2 red marbles as the previous one was red.
Since these are an "and" example you multiply these together to give the chance of two red ones: