Advertisements
Advertisements
Question
A box contains 10 red marbles, 20 blue marbles and 30 green marbles. 5 marbles are drawn at random. From the box, what is the probability that at least one is green?
Advertisements
Solution
Out of 60 marbles, five marbles can be drawn in 60C5 ways.
∴ Total number of elementary events = 60C5
P (no green) = \[\frac{\text{ Favourable outcomes} }{\text{ Total outcomes } }\]
= \[\frac{{}^{30} C_5}{{}^{60} C_5}\]
Thus, P(at least one green) = 1 – P (no green)
\[= 1 - \frac{^{30}{}{C}_5}{^{60}{}{C}_5}\]
\[ = 1 - \frac{117}{4484}\]
\[ = \frac{4484 - 117}{4484}\]
\[ = \frac{4367}{4484}\]
APPEARS IN
RELATED QUESTIONS
If `2/11` is the probability of an event, what is the probability of the event ‘not A’.
A letter is chosen at random from the word ‘ASSASSINATION’. Find the probability that letter is
- a vowel
- an consonant
If E and F are events such that P(E) = `1/4`, P(F) = `1/2` and P(E and F) = `1/8`, find
- P(E or F)
- P(not E and not F).
In Class XI of a school 40% of the students study Mathematics and 30% study Biology. 10% of the class study both Mathematics and Biology. If a student is selected at random from the class, find the probability that he will be studying Mathematics or Biology.
The probability that a student will pass the final examination in both English and Hindi is 0.5 and the probability of passing neither is 0.1. If the probability of passing the English examination is 0.75, what is the probability of passing the Hindi examination?
In a class of 60 students, 30 opted for NCC, 32 opted for NSS and 24 opted for both NCC and NSS. If one of these students is selected at random, find the probability that
- The student opted for NCC or NSS.
- The student has opted neither NCC nor NSS.
- The student has opted NSS but not NCC.
In a certain lottery, 10,000 tickets are sold and ten equal prizes are awarded. What is the probability of not getting a prize if you buy one ticket.
A dice is thrown. Find the probability of getting a multiple of 2 or 3.
In a simultaneous throw of a pair of dice, find the probability of getting a doublet of odd numbers
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 an even number on first
In a simultaneous throw of a pair of dice, find the probability of getting a sum more than 6
In a simultaneous throw of a pair of dice, find the probability of getting a sum more than 7
In a simultaneous throw of a pair of dice, find the probability of getting neither a doublet nor a total of 10
In a simultaneous throw of a pair of dice, find the probability of getting a number greater than 4 on each die
In a simultaneous throw of a pair of dice, find the probability of getting a total greater than 8.
In a single throw of three dice, find the probability of getting a total of 17 or 18.
Two dice are thrown. Find the odds in favour of getting the sum 4.
A box contains 6 red marbles numbered 1 through 6 and 4 white marbles numbered from 12 through 15. Find the probability that a marble drawn is white and odd numbered .
A box contains 6 red marbles numbered 1 through 6 and 4 white marbles numbered from 12 through 15. Find the probability that a marble drawn is even numbered
A box contains 6 red marbles numbered 1 through 6 and 4 white marbles numbered from 12 through 15. Find the probability that a marble drawn is red or even numbered.
If A and B are two events associated with a random experiment such that P(A) = 0.3, P (B) = 0.4 and P (A ∪ B) = 0.5, find P (A ∩ B).
There are three events A, B, C one of which must and only one can happen, the odds are 8 to 3 against A, 5 to 2 against B, find the odds against C
One of the two events must happen. Given that the chance of one is two-third of the other, find the odds in favour of the other.
A card is drawn at random from a well-shuffled deck of 52 cards. Find the probability of its being a spade or a king.
If the probability of A to fail in an examination is \[\frac{1}{5}\] and that of B is \[\frac{3}{10}\] . Then, the probability that either A or B fails is
A box contains 10 good articles and 6 defective articles. One item is drawn at random. The probability that it is either good or has a defect, is
Out of 30 consecutive integers, 2 are chosen at random. The probability that their sum is odd, is
Two dice are thrown simultaneously. The probability of getting a pair of aces is
One mapping is selected at random from all mappings of the set A = {1, 2, 3, ..., n} into itself. The probability that the mapping selected is one to one is
Three numbers are chosen from 1 to 20. The probability that they are not consecutive is
In a certain lottery 10,000 tickets are sold and ten equal prizes are awarded. What is the probability of not getting a prize if you buy two tickets.
