Answer:
It is the third option: (10C1) (20C1( / 50C2.
Step-by-step explanation:
The number of ways of selecting 2 marbles = the number of combination of any 2 marbles in the 50 marbles in the bag and this is 50C2. It is combinations because the order of drawing the marbles does not matter.
The number of combinations of one being red and the other blue = 10C1 times 20C1.
So the answer is (10C1) (20C1( / 50C2.
The answer should be 3 :)
Ping-pong ball, Volley Ball and Basketball
