So first add all of the marbles together: 3+2+6+9=20
Because there are 20 marbles together, that would be your denominator.
All of the other numbers would be your numerator. So you would have:
3/20 green marbles
2/20 yellow marbles
6/20 blue marbles
9/20 red marbles
So your answer would be the probability of picking a red marble from the bag is 9/20 or 45%
The answer is 6x, all u gotta do is add the 2 with the same variable (x)
It have more energy picking up more particles in less time
C. 4x + y = 21
4(3) + 9 = 21
12 + 9 = 21
21 = 21
