6.three persons A, B and C speak at a function along with 5 other persons speak at random, the probability that A speaks before B and B speaks before C is

7.Three of the six vertices of a regular hexagon are chosen at random. The probability that the triangle with three chosen vertices ais an equilateral triangle, is

8.A bag contains 6 balls of different colours and a ball is drawn from it. A probability of speaking the truth is 2/3 and B probability of speaking the truth is 4/5. If both A and B say that a red ball has been drawn then the probability that actually a red ball has been drawn, is

9.A pair of dice is rolled together till a sum of either 5 or 7 is obtained. The probability that 5 comes before 7, is

10.A box contains 24 identical balls of which 12 are white and remaining black. The balls are drawn at random from the box at a time with replacement. the probability that a white ball is drawn for the 4th time on the 7th draw, is