self Maths Puzzle

Four unit squares are chosen at random on a chessboard. What is the probability that three of them are of one colour and fourth is of opposite colour?

Read Solution (Total 1)

32C3 (1/2)^3 x 32C1(1/2)^1/ 64C4
9 years agoHelpfull: Yes(0) No(1)

self Other Question

Sum of digits of a 5 digit number is 41. Find the probability that such a number is divisible by 11?
A bag contains 10 balls numbered from 0 to 9. the balls are such that the person picking a ball out of the bag is equally likely to pick anyone of them. A person picked a ball and replaced it in the bag after noting its number. He repeated this process 2 more times. What is the probability that the ball picked first is numbered higher than the ball picked second and the ball picked second is numbered higher than the ball picked third?