CBSE - Probability

1 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 

2 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 

3 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 

4 Probability 

A die is thrown twice. The probability that 5 will not come up either of the time is :

(1) 35/36  
(2) 25/36 
(3) 1 / 36 
(4) 11/36

5 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

6 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 

7 Probability 

In a single throw of three dice, the probability of getting a total of 17 or 18 is 
 
1) 53/54
2) 51/54
3) 1/54 
4) 0 

8 Probability 

A die is thrown twice. The probability of the sum being odd, is
 
1) 1 / 2
2) 1 / 3
3) 1 / 4
4) 1 / 6 

9 Probability 

A die is thrown twice. Then the probability that 5 will come up at least once is  
 
1) 11/ 36
2) 7 / 36
3) 5 / 36 
4) 0 

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