UPSC previous year question paper of subject Permutation, Combination & Probability from the year 1996-2000 with answers.

Contents

- Results
- #1. A bag contains 20 balls, 8 balls are green, 7 are white and 5 are red. What is minimum number of balls that must be picked up from the bag blind-folded (without replacing any of it) to be assured of picking atleast one ball of each colour? [2000]
- #2. In a factory quality assurance test is conducted on various samples for a specific characteristic value of the product. The values and the number of samples are as given in the following table: [1999] Consider the following statements based on the table: 1. The probability that X £ 17 is 0.64 2. The probability that 15 19 < £ X is greater than 0.64 3. The probability that X = 15 is less than 0.22 Which of the above statements is/are not true?
- #3. When three coins are tossed together, the probability that all coins have the same face up, is [1997]
- #4. In the given figure, if QRS is an equilateral triangle and TQS is an isosceles triangle and x = 47°, then the value of y (in degrees) will be [1997]
- #5. Two packs of cards are thoroughly mixed and shuffled and two cards are drawn at random, one after the other. What is the probability that both of them are jacks? [1996]
- #6. X and Y are two variables whose values at Y time are related to each other as shown in Fig. (i). X is known to vary periodically with reference to time as shown in Fig. (ii) Which of the following curves depicts correctly the dependence of Y on time? [1995]
- #7. A table has three drawers. It is known that one of the drawers contains two silver coins, another contains two gold coins and the third one contains a silver coin and gold coin. One of the drawers is opened at random and a coin is drawn. It is found to be a silver coin. What is the probability that the other coin in the drawer is a gold coin? [1995]
- #8. A student has 60% chance of passing in English and 54% chance of passing in both English and Mathematics. What is the percentage probability that he will fail in Mathematics? [1995]