Elementary Statistics - Probability - General Aptitude (GA) Previous Year Questions

Approximate percentage of scores that fall within \(\pm \sigma\) (standard deviation) of the mean in a normal distribution is

Two policemen, A and B, fire once each at the same time at an escaping convict. The probability that A hits the convict is three times the probability that B hits the convict. If the probability of the convict not getting injured is 0.5, the probability that B hits the convict is

A coin is tossed ten times. The probability of getting five heads and five tails is ______.

A couple has 2 children. The probability that both children are boys if the older one is a boy is

A game consists of spinning an arrow around a stationary disk as shown below. When the arrow comes to rest, there are eight equally likely outcomes. It could come to rest in any one of the sectors numbered 1, 2, 3, 4, 5, 6, 7 or 8 as shown.
Two such disks are used in a game where their arrows are independently spun.
What is the probability that the sum of the numbers on the resulting sectors upon spinning the two disks is equal to 8 after the arrows come to rest?

A fair six-faced dice, with the faces labelled ‘1’, ‘2’, ‘3’, ‘4’, ‘5’, and ‘6’, is rolled thrice. What is the probability of rolling “6” exactly once?