problem archive
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It is given that in a group of 3 students, the probability of 2 students not having the same birthday is 0.992. What is the probability that the 2 stu... -
A bag contains 3 red balls and 5 black balls. A ball is drawn at random from the bag. What is the probability that the ball drawn is (i) red ? (ii) no... -
A box contains 5 red marbles, 8 white marbles and 4 green marbles. One marble is taken out of the box at random. What is the probability that the marb... -
A piggy bank contains hundred 50p coins, fifty ₹ 1 coins, twenty ₹ 2 coins and ten ₹ 5 coins. If it is equally likely that one of the coins will fall ... -
Gopi buys a fish from a shop for his aquarium. The shopkeeper takes out one fish at random from a tank containing 5 male fish and 8 female fish. What ... -
A game of chance consists of spinning an arrow which comes to rest pointing at one of the numbers 1, 2, 3, 4, 5, 6, 7, 8, and these are equally likely... -
A die is thrown once. Find the probability of getting (i) a prime number, (ii) a number lying between 2 and 6; (iii) an odd number. -
One card is drawn from a well-shuffled deck of 52 cards. Find the probability of getting (i) a king of red colour (ii) a face card (iii) a red face ca... -
Five cards—the ten, jack, queen, king and ace of diamonds, are well-shuffled with their face downwards. One card is then picked up at random. (i) What... -
12 defective pens are accidentally mixed with 132 good ones. It is not possible to just look at a pen and tell whether or not it is defective. One pen... -
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? (ii) Suppos... -
A box contains 90 discs which are numbered from 1 to 90. If one disc is drawn at random from the box, find the probability that it bears (i) a two-dig... -
A child has a die whose six faces show the letters as given below: [A, B, C, D, E, A]. The die is thrown once. What is the probability of getting (i) ... -
Suppose you drop a die at random on the rectangular region shown in Fig. 14.6. What is the probability that it will land inside the circle with diamet... -
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 defect... -
Refer to Example 13. (i) Complete the following table: [Table with Event: 'Sum on 2 dice' and Probability]. (ii) A student argues that 'there are 11 p... -
A game consists of tossing a one rupee coin 3 times and noting its outcome each time. Hanif wins if all the tosses give the same result i.e., three he... -
A die is thrown twice. What is the probability that (i) 5 will not come up either time? (ii) 5 will come up at least once? -
Which of the following arguments are correct and which are not correct? Give reasons for your answer. (i) If two coins are tossed simultaneously there... -
Write the solution set of the equation $x^2 + x - 2 = 0$ in roster form.