Probability

Two dice are tossed. The probability that the total score is a prime number is

• (1/6)

• (5/12)

• (1/2)

• (7/9)

If the probability that A Will live 15 years is (7/8) and that B Will live 15 years is (9/10), then what is the probability that both will live after 15 years?

• (1/20)

• (63/80)

• (1/5)

• None of these

In his wardrobe, Timothy has 3 trousers. One of them is black, the second blue, and the third brown. In his Wardrobe, he also has 4 shirts. One of them is black and the other 3 are White. He opens his Wardrobe in the dark and picks out one shirt-trouser pair, without examining the color. What is the likelihood that neither the shirt nor the trouser is black?

• (1/12)

• (1/6)

• (1/4)

• (1/2)

A class consists of 100 students, 25 of them are girls and 75 boys; 20 of them are rich and remaining poor, 40 of them are fair complexioned. The probability of selecting a fair complexioned rich girl is

• 0.05

• 0.04

• 0.02

• 0.08

A fair dice is tossed six times. Find the probability of getting a third six on the sixth throw.

• 5C2*52/66

• SP2*53/66

• 5C2*53/66

• 5P2*52/66

A bag contains 5 red ball and 8 blue balls. It also contains 4 green and 7 black balls. If a ball is drawn at random, then find the probability that it is not green.

• (5/6)

• (1/4)

• (1/4)

• (7/4)

An article manufactured by a company consists of two parts A and B. In the process of manufacture of part A, 9 or of 100 are likely to be defective. Similarly 5 out of 100 are likely to be

defective in the manufacture of part B. The probability that the assembled part will not be

defective, is

• 0.8645

• 0.9645

• 0.6243

• None of these

I forgot the last 3 digit of a 7-digit telephone number. If I randomly dial the final 3 digits after correctly dialing the first four, then what is the chance of dialing the correct number?

• (1/1001)

• (1/990)

• (1/999)

• (1/1000)

A box contains 6 white balls and 7 black balls. Two balls are drawn at random. What is the probability that both are of the same color?

• 5/13

• 6/13

• 7/13

• 6/7

A man and his wife appear in an interview for two vacancies in the same post. The probability of the husband's selection is 1/7 and the probability of the Wife's selection is 1/5. What is the probability that only one of them is selected?

• 4/5

• 2/7

• 8/15

• 4/7