Question

A bag contains five green marbles and 10 red marble what is the probability of selecting a green marble not replacing it and then the red marble

Answer 1

The required probability is
`(5)/(21)`.

Explanation:

We are given that,

Number of green marbles = 5

Number of red marbles = 10

Thus, total number of marbles = 5 + 10 = 15.

So, the probability of selecting a green marble =
`(5)/(15)=(1)/(3)`

Now, we are not replacing the green marble and then selecting a red marble.

So, one marble is removed from the total.

Then, the total number of marbles = 14

So, the probability of selecting a red marble =
`(10)/(14)=(5)/(7)`

Thus, the probability of selecting a green marble and then a red marble =
`(1)/(3)* (5)/(7)` =
`(5)/(21)`.

Thus, the required probability is
`(5)/(21)`.