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 

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

3 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 

4 Probability 

There are 30 cards of the same size in a bag on which natural numbers 1 to 30 are written. One card is taken out of the bag at random. Then the probability that the number on the selected card is not divisible by 3 is    
 
1) 1 / 3
2) 3 / 4
3) 2 / 3
4) 1 / 4

5 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
 

6 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 

7 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 

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 

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 

10 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