Question

There are 18 marbles in a bag, 4 are blue and 14 are yellow. Suppose you take a marble from the bag without looking. Then you take a second marble from the bag without looking. Find the probability that both marbles are blue. Express your answer as a fraction in simplest form.

Answer 1

`(2)/(51)`

Explanation:

We are given that

Total number of marbles=18

Blue marbles=4

Yellow marbles=14

We have to find the probability that the both marbles are blue.

Probability ,
`P(E)=(favorable\;cases)/(total\;number\;of\;cases)`

The probability of getting first blue marble =
`(4)/(18)`

It is without replacement.

Now remaining marbles=18-1=17

Blue marbles=4-1=3

The probability of getting second blue marble=
`(3)/(17)`

The probability that both marbles are blue=
`(4)/(18)* (3)/(17)=(2)/(51)`