Probability CBSE Questions & Answers

Probability

This is Mathematics Class 11 Probability CBSE Questions & Answers. There are 15 questions in this test with each question having around four answer choices.

Questions & Answers

1
An unbiased dice is rolled four times. The probability that the minimum number on any toss is not less than 3 is
  • A
    \({{16} \over {81}}\)
    Correct
  • B
    \({1 \over {81}}\)
  • C
    \({{65} \over {81}}\)
  • D
    \({{80} \over {81}}\)
2
The probability that a man will live for 10 more years is \({1 \over 4}\) and that his wife will live 10 more years is\({1 \over 3}\). The probability that neither will be alive in 10 years is
  • A
    \({1 \over 2}\)
    Correct
  • B
    \({{11} \over {12}}\)
  • C
    \({5 \over {12}}\)
  • D
    \({7 \over {12}}\)
3
The probability of having atleast one tail in five throws with a coin is
  • A
    \({1 \over {32}}\)
  • B
    \({1 \over 5}\)
  • C
    \({{31} \over {32}}\)
    Correct
  • D
    1
4
If E is any event associated with an experiment, then
  • A
    P (E) \( \ge \) 0
  • B
    P (E) \( \ge \)1
  • C
    P (E) \( \ge \) 0
  • D
    \(0 \le P\;(E) \le r\)
    Correct
5
A and B toss 3 coins. The probability that they both obtain the same number of heads is
  • A
    \({3 \over 8}\)
  • B
    \({3 \over {16}}\)
  • C
    \({1 \over 9}\)
  • D
    \({5 \over {16}}\)
    Correct
6
Three identical dice are rolled. The probability that the same number will appear on each of them is
  • A
    \({1 \over {18}}\)
  • B
    \({3 \over {28}}\)
  • C
    \({1 \over 6}\)
  • D
    \({1 \over {36}}\)
    Correct
7
Suppose n \(( \ge {\rm{3}})\) persons are sitting in a row. Two of them are selected at random. The probability that they are not together is
  • A
    \(n - {1 \over n}\)
  • B
    \({2 \over n} - 1\)
  • C
    none of these
  • D
    \(1 - {2 \over n}\)
    Correct
8
One ticket is selected at random from 100 tickets numbered 00, 01, 02…, 99. Suppose S and T are the sum and product of the digits of the number on the ticket, then the probability of getting S = 7 and T = 0 is
  • A
    \({1 \over {50}}\)
    Correct
  • B
    \({{19} \over {100}}\)
  • C
    \({1 \over 4}\)
  • D
    \({2 \over {19}}\)
9
A box contains 100 eggs out of which 4 are rotten. Two eggs are taken out together. If one of them is found to be good, the probability that other is also is
  • A
    \({1 \over 3}\)
  • B
    \({5 \over {13}}\)
    Correct
  • C
    \({8 \over {15}}\)
  • D
    \({2 \over 3}\)
10
A digit is selected at random from either of the two sets { 1, 2, 3, 4, 5, 6, 7, 8, 9} and {1, 2, 3, 4, 5, 6, 7, 8, 9{. What is the chance that the sum of the digits selected is 10 ?
  • A
    none of these
  • B
    \({1 \over 9}\)
    Correct
  • C
    \({{10} \over {81}}\)
  • D
    \({{10} \over {18}}\)
11
If two squares are chosen at random on a chess board, the probability that they have a side common is
  • A
    \({2 \over 7}\)
  • B
    \({1 \over {18}}\)
    Correct
  • C
    \({1 \over 9}\)
  • D
    none of these
12
A coin tail on both sides is tossed twice. The probability of getting ‘a head’ is
  • A
    1
  • B
    0
    Correct
  • C
    \({3 \over 4}\)
  • D
    \({1 \over 2}\)
13
The chance that an event E ‘occurs’ or does not occur’s
  • A
    1
    Correct
  • B
    0
  • C
    none of these
  • D
    2
14
Mean number of ‘sixes’ in four throws of a fair dic is
  • A
    \({4 \over 6}\)
    Correct
  • B
    1
  • C
    \({1 \over 4}\)
  • D
    \({6 \over 4}\)
15
From a deck of 52 cards, the probability of drawing a court card is
  • A
    \({1 \over {13}}\)
  • B
    \({4 \over {13}}\)
  • C
    \({3 \over {13}}\)
    Correct
  • D
    \({1 \over 4}\)