whenever Suzan sees a bag of marbles she grabs a handful at

whenever Suzan sees a bag of marbles, she grabs a handful at random. She has seen a bag containing three red marbles, three green ones, five white ones, and three purple ones. She grabs seven of them. Find the probability of the following event, expressing it as a fraction in lowest terms.

____ she has all red ones

Solution

Here there are only 3 red marbles.
Total marbles in the bag = 3 + 5 + 3= 11
She draws 7 marbles from the bag.
As there are only 3 red marbles in the bag, all 7 cannot be red.
This is an impossible event.

Hence the probability of having all red marbles = 0 .......Answer