CBSE Board Practice

Class VI Class VII Class VIII Class IX Class X
CBSE Grade IX - Probability
Question 1
1.
A coin is tossed 40 times and head appears 25 times. If the coin is tossed again, what is the probability of getting a tail?
  • 5
    8
  • 1
    2
  • 1
    4
  • 3
    8
  • 4
    9
Question 2
2.
    • 234 families with 2 children were selected randomly, and the following data were recorded
    • No. of girls in a family
      0
      1
      2
      Number of families
      45
      90
      99
    • Compute the probability of the family, chosen at random, having 1 girl.
  • 8
    13
  • 6
    13
  • 3
    7
  • 5
    13
  • 4
    13
Question 3
3.
A coin is tossed 60 times and tail appears 35 times. If the coin is tossed again, what is the probability of getting a head?
  • 5
    12
  • 6
    13
  • 7
    12
  • 1
    2
  • 1
    3
Question 4
4.
A die is thrown 530 times. The number 6 appears on the upper face 86 times. Now the die is thrown at random. What is the probability of getting a 6 ?
  • 44
    265
  • 42
    265
  • 22
    133
  • 222
    265
  • 43
    265
Question 5
5.
There are 52 students in a class room of whom 24 are boys and 28 are girls. From these students, one is choosen at random. What is the probability that the choosen student is a girl ?
  • 8
    13
  • 6
    13
  • 7
    13
  • 4
    7
Question 6
6.
    • On a particular day, at a crossing in a city, the various types of 105 vehicles going past during a time-interval were observed as under:
    • Type of Vehicle
      Two-wheeler
      Four-wheeler
      Three-wheeler
      Frequency
      25
      35
      45
    • Out of these vehicles, if one is choosen at random, what is the probability that the choosen vehicle is a 'Two-wheeler' ?
  • 16
    21
  • 3
    11
  • 5
    21
  • 2
    7
  • 4
    21
Question 7
7.
Two coins are tossed simultaneously 40 times and it was observed that both tails appeared 20 times. If two coins are tossed simultaneously at random, what is the probability of getting both tails?
  • 4
    5
  • 2
    3
  • 3
    4
  • 1
    2
  • 5
    6
Question 8
8.
    • Three coins are tossed simultaneously 140 times with the following frequencies of different outcomes :
    • Outcome
      3 heads
      2 heads
      1 heads
      No heads
      Frequency
      25
      30
      40
      45
    • If the three coins are simultaneously tossed again, compute the probability of '2 heads' coming up.
  • 11
    14
  • 1
    7
  • 3
    14
  • 4
    15
  • 2
    7
Question 9
9.
Two coins are tossed simultaneously 80 times and it was observed that both heads appeared 60 times. If two coins are tossed simultaneously at random, what is the probability of getting both heads?
  • 4
    5
  • 1
  • 1
    4
  • 3
    4
  • 1
    2
Question 10
10.
A survey of 60 men showed that only 35 of them know Sanskrit. Out of these men, if one is selected at random, what is the probability that the selected man knows Sanskrit?
  • 2
    3
  • 1
    2
  • 8
    13
  • 5
    12
  • 7
    12