Advertisements
Advertisements
प्रश्न
A box contains cards bearing numbers 6 to 70. If one card is drawn at random from the box, find the probability that it bears an odd number less than 30.
उत्तर
Let E3 be the event of getting an odd number less than 30.
Out of these numbers, odd numbers less than 30 are 7, 9, 11, ... , 29.
Given number 7, 9, 11, .... , 29 form an AP with a = 7 and d = 2.
Let Tn = 29. Then,
7 + (n − 1)2 = 29
⇒ 7 + 2n − 2 = 29
⇒ 2n = 24
⇒ n = 12
Thus, number of favourable outcomes = 12.
∴ P(getting an odd number less than 30) = P(E3) = `("Number of outcomes favourable to" E_3)/"Number of all possible outcomes"`
Thus, the probability that the card bears an odd number less than 30 is `12/65`.
APPEARS IN
संबंधित प्रश्न
There are 40 students in a class of whom 25 are girls and 15 are boys. The class teacher has to select one student as a class representative. He writes the name of each student on a separate card, the cards being identical. Then she puts cards in a bag and stirs them thoroughly. She then draws one card from the bag. What is the probability that the name written on the card is the name of a girl ?
There are 40 students in a class of whom 25 are girls and 15 are boys. The class teacher has to select one student as a class representative. He writes the name of each student on a separate card, the cards being identical. Then she puts cards in a bag and stirs them thoroughly. She then draws one card from the bag. What is the probability that the name written on the card is the name of a boy ?
One card is drawn from a well-shuffled deck of 52 cards. Find the probability of drawing an ace.
Cards bearing numbers 1, 3, 5, .... , 35 are kept in a bag. A card is drawn at random from the bag. Find the probability of getting a card bearing a prime number less than 15,
A box contains cards bearing numbers 6 to 70. If one card is drawn at random from the box, find the probability that it bears a one-digit number,
Find the probability that a leap year selected at random will contain 53 Sundays.
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 7, is
Which of the following cannot be the probability of an event?
The probability of throwing a number greater than 2 with a fair die is
A carton of 24 bulbs contain 6 defective bulbs. One bulbs is drawn at random. What is the probability that the bulb is not defective? If the bulb selected is defective and it is not replaced and a second bulb is selected at random from the rest, what is the probability that the second bulb is defective?
