CBSE - Probability

1 Probability 

Two dice are tossed. The  probability that the  total sum is a prime number is:  
 
1) 1 / 6
2) 5 / 12
3) 1 / 2
4) 7 / 9 

2 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

3 Probability 

A letter is chosen at random from the word “probability”. The probability that it is a vowel is  
 
1) 1 / 11
2) 2 / 11
3) 3 / 11
4) 4 / 11

4 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 

5 Probability 

A bag contains 2 red, 3 green and 2 blue  balls. Two balls are drawn at random. What is the probability that none  of the balls drawn is blue? 
 
1)  10 / 21
2)  11 / 21
3)  2 / 7
4) 5 / 7 

6 Probability 

In a class, there are 15 boys and 10 girls. Three students are selected at random. The probability that 1 girl and 2 boys are selected, is: 
 
1) 21 / 46
2) 25 / 117
3) 1 / 50
4) 3 / 25 

7 Probability 

Two cards are drawn together from a pack of 52 cards. The probability that one is  a spade and other is a heart, is :    
 
1) 3 / 20
2) 29 / 34
3) 47 / 100
4) 13 / 102 

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 

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 

10 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