Question

A box contains red marbles. 8 green marbles 4 blue marbles and 3 yellow marbles. If 2 marbles are randomly selected without replacement, what is the probability that a red marble is selected and then a green marble is selected?

Answer 1

0.1052 = 10.52%

Explanation:

The question missing the number of red marbles, it should be 5.

You select 2 marble randomly without replacement. The word without replacement show that you pick the marble at different times, so the order is important. There are 5 red, 8 green, 4 blue, 3 yellow which means the total marble is 8+4+3= 16 marbles. The chance to pick red marble then a green marble will be:

5/20 * 8/19= 2/19= 0.1052 = 10.52%