Probability Tes...

If n integers taken at random are multiplied together, then the probability that the last digit of the product is 1, 3, 7 or 9, is

A fair die is thrown twenty times. The probability that on the tenth throw the fourth six appears is

Four fair dice D₁, D₂, D₃ and D₄ each having six faces numbered 1, 2, 3, 4, 5 and 6 are rolled, simultaneously. the probability that D₄ shows a number appearing on one of D₁, D₂, and D₃ is

Probability of product of a perfect square when 2 dice are thrown together, is

A card is drawn from a well shuffled pack of playing cards. The probability that it is a heart of a king, is

The probability that a leap year will have only 52 Sunday, is

A bag has four pair of balls of four distinct colours. If four balls are picked at random (without replacement), the probability that there is atleast one pair among them have the same colour is

Let ω be a complex cube root of unity with ω ≠ 1. A fair die is thrown three times. If r₁, r₂ and r₃ are the numbers obtained on the die, then the probability that

Four numbers are chosen at random (without replacement) from the set {l, 2, 3, ... , 20}.
Statement I The probability that the chosen numbers when arranged in some order will form an AP is 1/85.
Statement II If the four chosen numbers form an AP, then the set of all possible values of common difference is {± 1, ± 2, ± 3, ± 4, ± 5}.

If birth to male child and birth to female child are equal probable, then what is the probability that atleast one of the three children born to a couple is male?