Advertisements
Advertisements
Question
20 cards are numbered from 1 to 20. One card is drawn at random. What is the probability that the number on the cards is divisible by 5?
Solution
Clearly, the sample space is given by S = {1, 2, 3, 4, 5........19, 20}.
i.e. n(S) = 20
Let E5 = event of getting a number divisible by 5
Then E5 = {5, 10, 15, 20}
i.e. n(E5) = 4
Hence, required probability = P(E5) = \[\frac{4}{20} = \frac{1}{5}\]
APPEARS IN
RELATED QUESTIONS
One die of red colour, one of white colour and one of blue colour are placed in a bag. One die is selected at random and rolled, its colour and the number on its uppermost face is noted. Describe the sample space.
An experiment consists of tossing a coin and then throwing it second time if a head occurs. If a tail occurs on the first toss, then a die is rolled once. Find the sample space.
A coin is tossed. If the out come is a head, a die is thrown. If the die shows up an even number, the die is thrown again. What is the sample space for the experiment?
The numbers 1, 2, 3 and 4 are written separately on four slips of paper. The slips are put in a box and mixed thoroughly. A person draws two slips from the box, one after the other, without replacement. Describe the sample space for the experiment.
A coin is tossed. If it shows a tail, we draw a ball from a box which contains 2 red and 3 black balls. If it shows head, we throw a die. Find the sample space for this experiment.
If a coin is tossed two times, describe the sample space associated to this experiment.
What is the total number of elementary events associated to the random experiment of throwing three dice together?
A coin is tossed and then a die is thrown. Describe the sample space for this experiment.
A coin is tossed and then a die is rolled only in case a head is shown on the coin. Describe the sample space for this experiment.
An experiment consists of tossing a coin and then tossing it second time if head occurs. If a tail occurs on the first toss, then a die is tossed once. Find the sample space.
A coin is tossed. Find the total number of elementary events and also the total number events associated with the random experiment.
A card is drawn at random from a pack of 52 cards. Find the probability that the card drawn is a black king
A card is drawn at random from a pack of 52 cards. Find the probability that the card drawn is neither a heart nor a king
A card is drawn at random from a pack of 52 cards. Find the probability that the card drawn is spade or an ace
A card is drawn at random from a pack of 52 cards. Find the probability that the card drawn is not a black card.
From a deck of 52 cards, four cards are drawn simultaneously, find the chance that they will be the four honours of the same suit.
A bag contains 6 red, 4 white and 8 blue balls. If three balls are drawn at random, find the probability that two are blue and one is red
A committee of two persons is selected from two men and two women. What is the probability that the committee will have no man?
A committee of two persons is selected from two men and two women. What is the probability that the committee will have one man?
20 cards are numbered from 1 to 20. One card is drawn at random. What is the probability that the number on the cards is a multiple of 4?
20 cards are numbered from 1 to 20. One card is drawn at random. What is the probability that the number on the cards is not a multiple of 4?
20 cards are numbered from 1 to 20. One card is drawn at random. What is the probability that the number on the cards is odd?
20 cards are numbered from 1 to 20. One card is drawn at random. What is the probability that the number on the cards is not a multiple of 6?
Five cards are drawn from a well-shuffled pack of 52 cards. Find the probability that all the five cards are hearts.
A bag contains tickets numbered from 1 to 20. Two tickets are drawn. Find the probability that both the tickets have prime numbers on them
An urn contains 7 white, 5 black and 3 red balls. Two balls are drawn at random. Find the probability that both the balls are red .
Two cards are drawn from a well shuffled pack of 52 cards. Find the probability that either both are black or both are kings.
Two dice are thrown simultaneously. The probability of obtaining a total score of 5 is
Six boys and six girls sit in a row randomly. The probability that all girls sit together is
6 boys and 6 girls sit in a row at random. The probability that all the girls sit together is
Three digit numbers are formed using the digits 0, 2, 4, 6, 8. A number is chosen at random out of these numbers. What is the probability that this number has the same digits?
An ordinary deck of cards contains 52 cards divided into four suits. The red suits are diamonds and hearts and black suits are clubs and spades. The cards J, Q, and K are called face cards. Suppose we pick one card from the deck at random. What is the event that the chosen card is a black face card?
How many two-digit positive integers are multiples of 3?
What is the probability that a randomly chosen two-digit positive integer is a multiple of 3?
An urn contains nine balls of which three are red, four are blue and two are green. Three balls are drawn at random without replacement from the urn. The probability that the three balls have different colours is ______.
Five horses are in a race. Mr. A selects two of the horses at random and bets on them. The probability that Mr. A selected the winning horse is ______.