Advertisements
Advertisements
प्रश्न
- A lot of 20 bulbs contain 4 defective ones. One bulb is drawn at random from the lot. What is the probability that this bulb is defective?
- Suppose the bulb drawn in (1) is not defective and is not replaced. Now one bulb is drawn at random from the rest. What is the probability that this bulb is not defective?
उत्तर
(i) Total number of bulbs = 20
∴ Total number of defective bulbs = 4
P (getting a defective bulb) = `4/20 = 1/5`
(ii) Remaining total number of bulbs = 20 − 1 = 19
Total number of possible outcome = 19
Remaining total number of non-defective bulbs = 16 − 1 = 15
∴ Number of favourable outcomes = 15
`"Number of favourable outcomes"/"Total number of possible outcomes" = 15/19`
P (getting a not defective bulb) = `15/19`
APPEARS IN
संबंधित प्रश्न
In a simultaneous throw of a pair of dice, find the probability of getting a sum greater than 9
In a simultaneous throw of a pair of dice, find the probability of getting a sum more than 7
A bag contains 5 black, 7 red and 3 white balls. A ball is drawn from the bag at random. Find the probability that the ball drawn is black or white
Five cards—ten, jack, queen, king, and an ace of diamonds are shuffled face downwards.One card is picked at random If a king is drawn first and put aside, what is the probability that the second card picked up is the ace?
In a class, there are 18 girls and 16 boys. The class teacher wants to choose one pupil form class monitor. What she does, she writes the name of each pupil on a card and puts them into a basket and mixes thoroughly. A child is asked to pick one card from the basket. What is the probability that the name written on the card is the name of a girl?
From a pack of 52 playing cards Jacks, queens, kings and aces of red colour are removed. From the remaining, a card is drawn at random. Find the probability that the card drawn is a picture card (Jacks, queens and kings are picture cards)
A lot consists of 144 ball pens, of which 20 are defective and the others are good. Nuri will buy a pen if it is good, but will not buy if it is defective. The shopkeeper draws one pen at random and gives it to her. What is the probability that she will not buy it?
From a deck of 52 cards, all the face cards are removed and then the remaining cards are shuffled. Now one card is drawn from the remaining deck. Find the probability that the card drawn is 8 of red color.
From a well-shuffled deck of 52 cards, one card is drawn. Find the probability that the card drawn is a queen of black card.
There are six cards in a box, each bearing a number from 0 to 5. Find the probability of the following event, that a card drawn show, a natural number.
A number is selected at random from the numbers 1 to 30. What is the probability that the selected number is a prime number?
A bag contains 3 white, 4 red and 5 black balls. One ball is drawn at random. What is the probability that the ball drawn is neither black nor white?
Namita tossed a coin once. What is the probability of getting Head?
Two dice are thrown simultaneously. Find the probability of getting: an even number as the sum.
A letter of English alphabets is chosen at random. What is the probability that it is a letter of the word ‘MATHEMATICS’?
A card is drawn from a deck of 52 cards. The event E is that card is not an ace of hearts. The number of outcomes favourable to E is ______.
One ticket is drawn at random from a bag containing tickets numbered 1 to 40. The probability that the selected ticket has a number which is a multiple of 5 is ______.
Someone is asked to take a number from 1 to 100. The probability that it is a prime is ______.
The king, queen and jack of clubs are removed from a deck of 52 playing cards and then well shuffled. Now one card is drawn at random from the remaining cards. Determine the probability that the card is a heart.
A card is drawn at random from a well shuffled deck of 52 playing cards. The probability of getting a face card is ______.
