English

If the probabilities for A to fail in an examination is 0.2 and that for B is 0.3, then the probability that either A or B fails is ______. - Mathematics

Advertisements
Advertisements

Question

If the probabilities for A to fail in an examination is 0.2 and that for B is 0.3, then the probability that either A or B fails is ______.

Options

  • > 0.5

  • 0.5

  • ≤ 0.5

  • 0

MCQ
Fill in the Blanks
Advertisements

Solution

If the probabilities for A to fail in an examination is 0.2 and that for B is 0.3, then the probability that either A or B fails is ≤ 0.5.

Explanation:

Given that: P(A fails) = 0.2

P (B fails) = 0.3

∴ P(either A or B fails) ≤ P(A fails) + P(B fails)

≤ 0.2 + 0.3

≤ 0.5

shaalaa.com
  Is there an error in this question or solution?
Chapter 16: Probability - Exercise [Page 300]

APPEARS IN

NCERT Exemplar Mathematics [English] Class 11
Chapter 16 Probability
Exercise | Q 27 | Page 300

Video TutorialsVIEW ALL [1]

RELATED QUESTIONS

Which of the following can not be valid assignment of probabilities for outcomes of sample space S = {ω1, ω2,ω3,ω4,ω5,ω6,ω7}

Assignment ω1 ω2 ω3 ω4 ω5 ω6 ω7
(a) 0.1 0.01 0.05 0.03 0.01 0.2 0.6
(b) `1/7` `1/7` `1/7` `1/7` `1/7` `1/7` `1/7`
(c) 0.1 0.2 0.3 0.4 0.5 0.6 0.7
(d) –0.1 0.2 0.3 0.4 -0.2 0.1 0.3
(e) `1/14` `2/14` `3/14` `4/14` `5/14` `6/14` `15/14`

A coin is tossed twice, what is the probability that at least one tail occurs?


A die is thrown, find the probability of following events:

  1. A prime number will appear,
  2. A number greater than or equal to 3 will appear,
  3. A number less than or equal to one will appear,
  4. A number more than 6 will appear,
  5. A number less than 6 will appear.

A fair coin with 1 marked on one face and 6 on the other and a fair die are both tossed. Find the probability that the sum of numbers that turn up is (i) 3 (ii) 12


A fair coin is tossed four times, and a person win Re 1 for each head and lose Rs 1.50 for each tail that turns up.

From the sample space calculate how many different amounts of money you can have after four tosses and the probability of having each of these amounts.


Three coins are tossed once. Find the probability of getting

  1. 3 heads
  2. 2 heads
  3. at least 2 heads
  4. at most 2 heads
  5. no head
  6. 3 tails
  7. exactly two tails
  8. no tail
  9. atmost two tails.

In a lottery, person chooses six different natural numbers at random from 1 to 20, and if these six numbers match with the six numbers already fixed by the lottery committee, he wins the prize. What is the probability of winning the prize in the game? [Hint: order of the numbers is not important.]


A and B throw a pair of dice. If A throws 9, find B's chance of throwing a higher number.

 

Two unbiased dice are thrown. Find the probability that the total of the numbers on the dice is greater than 10.

 

Two unbiased dice are thrown. Find the probability that the sum of the numbers obtained on the two dice is neither a multiple of 2 nor a multiple of 3


If a letter is chosen at random from the English alphabet, find the probability that the letter is  a vowel .


Which of the cannot be valid assignment of probability for elementary events or outcomes of sample space S =  {w1w2w3w4w5w6w7}:

Elementary events: w1 w2 w3 w4 w5 w6 w7
(i) 0.1 0.01 0.05 0.03 0.01 0.2 0.6

Which of the cannot be valid assignment of probability for elementary events or outcomes of sample space S =  {w1w2w3w4w5w6w7}:

Elementary events: w1 w2 w3 w4 w5 w6 w7
(ii)
\[\frac{1}{7}\]
\[\frac{1}{7}\]
\[\frac{1}{7}\]
\[\frac{1}{7}\]
\[\frac{1}{7}\]
\[\frac{1}{7}\]
\[\frac{1}{7}\]

Which of the cannot be valid assignment of probability for elementary events or outcomes of sample space S =  {w1w2w3w4w5w6w7}:

Elementary events: w1 w2 w3 w4 w5 w6 w7
(iii) 0.7 0.06 0.05 0.04 0.03 0.2 0.1

A box contains 100 bulbs, 20 of which are defective. 10 bulbs are selected for inspection. Find the probability that: all 10 are defective


Two dice are thrown together. The probability that neither they show equal digits nor the sum of their digits is 9 will be


Three squares of chessboard are selected at random. The probability of getting 2 squares of one colour and other of a different colour is ______.


If the letters of the word ALGORITHM are arranged at random in a row what is the probability the letters GOR must remain together as a unit?


Six new employees, two of whom are married to each other, are to be assigned six desks that are lined up in a row. If the assignment of employees to desks is made randomly, what is the probability that the married couple will have nonadjacent desks?


The accompanying Venn diagram shows three events, A, B, and C, and also the probabilities of the various intersections (for instance, P(A ∩ B) = .07). Determine P(A ∪ B)


The accompanying Venn diagram shows three events, A, B, and C, and also the probabilities of the various intersections (for instance, P(A ∩ B) = .07). Determine P(B ∩ C)


A bag contains 8 red and 5 white balls. Three balls are drawn at random. Find the probability that all the three balls are red


A bag contains 8 red and 5 white balls. Three balls are drawn at random. Find the probability that all one ball is red and two balls are white


If the letters of the word ASSASSINATION are arranged at random. Find the probability that four S’s come consecutively in the word


If the letters of the word ASSASSINATION are arranged at random. Find the probability that no two A’s are coming together


Three numbers are chosen from 1 to 20. Find the probability that they are not consecutive ______.


Seven persons are to be seated in a row. The probability that two particular persons sit next to each other is ______.


The probability that a person visiting a zoo will see the giraffee is 0.72, the probability that he will see the bears is 0.84 and the probability that he will see both is 0.52.


The probability that a student will pass his examination is 0.73, the probability of the student getting a compartment is 0.13, and the probability that the student will either pass or get compartment is 0.96.


The probabilities that a typist will make 0, 1, 2, 3, 4, 5 or more mistakes in typing a report are, respectively, 0.12, 0.25, 0.36, 0.14, 0.08, 0.11. 


If A and B are two candidates seeking admission in an engineering College. The probability that A is selected is .5 and the probability that both A and B are selected is at most .3. Is it possible that the probability of B getting selected is 0.7?


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×