3 yellow + 7 green = 10 total marbles.
The probability of picking a certain color is the number of that color over the total quantity.
Picking yellow would be 3 yellow / 10 total = 3/10
Picking green would be 7 green / 10 total = 7/10
To find the probability of doing both multiply the probability of each one by each other:
3/10 x 7/10 = 21/100
The answer would be 21/100
