Probability (SSC)

Total Questions: 64

11. A man is known to speak the truth 5 out of 8 times. He throws a dice and reports that it is a four. Find the probability that it is actually a four?

Correct Answer: (c)
Solution:

12. If the odds in favour of an event A are 3 : 4 and the odds against another independent event B are 7 : 4 find the probability that at least one of the event will happen :

Correct Answer: (b)
Solution:

13. If from each of the three boxes containing 3 white and 1 black, 2 white and 2 black, 1 white and 3 black balls, one ball is drawn at random, then the probability that 2 white and 1 black ball will be drawn is :-

Correct Answer: (a)
Solution:

14. A bag contains 4 purple, 1 white and 2 blue balls. Two balls are drawn at random. What is the probability that none of the balls drawn is blue?

Correct Answer: (b)
Solution:

15. What is the probability of getting all heads, when 3 coins are tossed simultaneously

Correct Answer: (d)
Solution:

16. A bag contains 3 red and 7 black balls. Two balls are taken out at random, without replacement. If the first ball is red, then what is the probability that the second ball is also red ?

Correct Answer: (b)
Solution:

17. A jar contains 3 red marbles, 7 green marbles and 10 white marbles. If 2 marble is drawn from the jar at random, what is the probability that this marble is white?

Correct Answer: (a)
Solution:

18. If a number of two digits is formed with the digits 4, 3, 5, 8, 6 without repetition of digits, what is the probability that the number formed is 46?

Correct Answer: (b)
Solution:

19. A bag contains cards numbered from 33 to 92 . If one card is drawn from a bag. The probability that the number on the drawn card is a perfect square is :

Correct Answer: (a)
Solution:

20. A bag contains 4 white and 6 red balls. Three balls are drawn at random. What is the probability that two balls are white and 1 is red ?

Correct Answer: (b)
Solution: