CBSE - Probability

1 Probability 

 A bag contains 10 red balls and some white balls. If the probability of drawing a white ball is double that of a red ball, then number of white balls in the bag will be 
 
1) 10
2) 15
3) 20 
4) 25 

2 Probability 

Mallica and Deepica are friends. Then the probability that both have same birthday is (ignoring aleap year)  
 
1) 364 / 365
2) 1 / 365
3) 363 / 365 
4) 2 / 365 

3 Probability 

 Three unbiased coins are tossed together. Then the probability of getting at least one head and one tail is   
 
1) 1 / 4
2) 1
3) 3 / 4 
4) 0 

4 Probability 

 A game consists of tossing a one rupee coin 3 times and noting its outcome each time. Hanif wins if all the tosses give the same result i.e., three heads or three tails, and loses otherwise. Calculate the probability that Hanif will lose the game.  
 
1) 1 / 4
2) 1
3) 3 / 4 
4) 0 

5 Probability 

The king, queen and jack of hearts are removed from a deck of 52 playing cards and then wellshuffled. One card is selected from the remaining cards. Then the probability of getting a king is  
 
1)  1 / 49
2)  2 / 49
3)  3 / 49 
4) 1 

6 Probability 

Tickets numbered 1 to 20 are mixed up and then a ticket is drawn at random. What is the probability that the ticket drawn has a number which is a multiple of 3 or 5? 
1)  1 / 2
2)  2 / 5
3)  8/ 15
4) 9 / 20
 

7 Probability 

There are 50 cards maked with the numbers 1 to 50. One card is drawn at random. What is the probability that number on the card is a prime number ?

1) 3 /10
2) 1 / 5
3) 1 / 4
4) 2 /15

8 Probability 

Out of a day’s production, which is 1000 machine  parts, 100 we re  found to be  sub-standard. The  probability that a part se le cte d at random be ing up to the  standard is
 
1) 1 / 10
2) 9 / 10
3) 2 / 10
4) 5 / 10

9 Probability 

 Probability that a non leap year should have 53 Mondays, will be  
 
1) 2 / 7
2) 3 / 7
3) 1 / 7
4) 5 / 7

10 Probability 

Box A contains 30% first grade articles. Box B contains 40% first grade articles. One article is draw from each box. Then the probability that both articles drawn are first grade is   
 
1) 1 / 25
2) 3 / 25
3) 7 / 25 
4) 9 / 25