CBSE Board Practice

Class VI Class VII Class VIII Class IX Class X
CBSE Grade IX - Probability
Question 1
1.
    • Three coins are tossed simultaneously 245 times with the following frequencies of different outcomes :
    • Outcome
      3 heads
      2 heads
      1 heads
      No heads
      Frequency
      40
      50
      70
      85
    • If the three coins are simultaneously tossed again, compute the probability of '2 heads' coming up.
  • 11
    49
  • 11
    50
  • 10
    49
  • 39
    49
  • 9
    49
Question 2
2.
There are 60 students in a class room of whom 24 are boys and 36 are girls. From these students, one is choosen at random. What is the probability that the choosen student is a girl ?
  • 4
    5
  • 2
    3
  • 3
    5
  • 2
    5
Question 3
3.
In a lottery, there are 18 prizes and 13 blanks. What is the probability of not getting a prize?
  • 14
    31
  • 12
    31
  • 13
    31
  • 18
    31
  • 7
    16
Question 4
4.
Two coins are tossed simultaneously 60 times and it was observed that both heads appeared 35 times. If two coins are tossed simultaneously at random, what is the probability of getting both heads?
  • 1
    2
  • 8
    13
  • 5
    12
  • 7
    12
  • 2
    3
Question 5
5.
A coin is tossed 80 times and head appears 50 times. If the coin is tossed again, what is the probability of getting a tail?
  • 3
    8
  • 4
    9
  • 1
    2
  • 1
    4
  • 5
    8
Question 6
6.
    • The distances (in km) of engineers from their residence to their place of work were found as follows
      • 23
      • 16
      • 2
      • 15
      • 29
      • 6
      • 2
      • 25
      • 18
      • 11
      • 6
      • 25
    • What is the empirical probability that an engineer lives greater than 11 km from her place of work?
  • 1
    2
  • 8
    13
  • 7
    12
  • 2
    3
  • 5
    12
Question 7
7.
    • The distances (in km) of engineers from their residence to their place of work were found as follows
      • 4
      • 30
      • 14
      • 13
      • 5
      • 26
      • 27
      • 28
      • 16
      • 29
      • 5
      • 22
      • 20
      • 8
      • 20
    • What is the empirical probability that an engineer lives less than 30 km from her place of work?
  • 13
    15
  • 15
    16
  • 14
    15
  • 1
  • 1
    15
Question 8
8.
A survey of 120 men showed that only 45 of them know English. Out of these men, if one is selected at random, what is the probability that the selected man knows English?
  • 5
    8
  • 4
    9
  • 1
    2
  • 3
    8
  • 1
    4
Question 9
9.
    • On a particular day, at a crossing in a city, the various types of 195 vehicles going past during a time-interval were observed as under:
    • Type of Vehicle
      Two-wheeler
      Four-wheeler
      Three-wheeler
      Frequency
      55
      65
      75
    • Out of these vehicles, if one is choosen at random, what is the probability that the choosen vehicle is a 'Four-wheeler' ?
  • 1
    2
  • 2
    3
  • 0
  • 1
    3
Question 10
10.
    • A die is thrown 450 times with the frequencies for outcomes 1, 2, 3, 4, 5 and 6 as given in the following table
    • Outcome
      1
      2
      3
      4
      5
      6
      Frequency
      30
      65
      80
      85
      90
      100
    • If the die is thrown again randomly, find the probability of getting 1 as outcome.
  • 1
    8
  • 1
    15
  • 14
    15
  • 0
  • 2
    15