A bag contains 2+2+4=8 marbles in total.
We have to find the probability of the following events:
1. We have to choose a red marble from the bag that contains 8 marbles in total, 2 of them are red
2. We have to choose a green marble from the bag that contains 7 marbles in total, 2 of them are green.
The probability of the first event to happens is:

The probability of the second event to happen is:

The probability of both events to happen is:
