Question

Three ceramic jars contain some white and some black marbles. The number of read black marbles in Jar 1 is in the ratio 5 : 6 and total number of marbles in it are 55. The number of black marbles in Jar 3 is equal to number of black marbles in Jar 1 and number of white marbles in Jar 2 is 5 less than number of white marbles in Jar 1. If Jar 2 and Jar 3 contains 65 and 45 marbles respectively. Then the sum of difference of probabilities of getting white and black marbles from the three jars is

Answer 1

The probability of choosing green marble as first marble is

4+5+1+2

1

=

12

1

The green marble is replaced.

The probability of choosing red marble as second marble is

4+5+1+2

5

=

12

5

The probability of choosing a green marble and then a red marble is

12

1

×

12

5

=

144

5