ASSIGNMENT 4
PROBABILITY: CLASS X
2. If two dice are thrown simultaneously then what is the total number of outcomes.
3. A throws a coin twice . What is the probability of getting a Head both the times.
4. The sum of the probability of an event happening is 0.6. Then what is the probability of it not happening.
5. An unbiased die is thrown. What is the probability of getting? (i) an even number? (ii) a multiple of 5? (iii) an even number or a multiple of 3? (iv) a multiple of 2 and 3?
6. Two dice are thrown simultaneously. What is the probability of getting? (i) an odd number as the sum? (ii) a total of at least 10? (iii) the same number on both dice? (iv) a sum greater then 10?
7. Find that the probability of a leap year selected at random will contain 53 Mondays.
8. All the face cards are removed from a pack of 52 cards and are then shuffled well. One card is selected from the remaining cards. What is the probability of
(i) getting an ace?
(ii) getting a red card?
(iii) getting 10 of spade?
(iv) getting a number less than 5?
9. A bag contains five red balls and some white balls. If the probability of drawing a white ball is double that of a red ball, find the number of white balls in the bag.
10. A bag contains 20 balls out of which ‘x’ are red. (i) If one ball is drawn at random, what is the probability that it will not be a white ball? (ii) If five more red balls are added, the probability of drawing a red ball will become 40%. Find the number of balls which are not red.
11. 1000 tickets of a lottery were sold and there are three prizes in the lottery. If Sachin has purchased one ticket, what is the probability of his winning a prize?
12. 26 cards marked with English letters A to Z (one letter on each card) are shuffled well. If one card is selected at random, what is the probability of getting?
(i) a vowel?
(ii) a letter in the word PROBABILITY?
13. While shuffling a pack of 52 cards, Khushi dropped one card by mistake. What is the probability of the dropped card being a red queen?
14. A circle of diameter 7 cm is drawn inside A rectangle of dimensions 15 cm × 7 cm . If a coin is dropped randomly inside the rectangle, what is the probability that the coin lands inside the circle?
15. Mohan and Salim are friends. What is the probability that both will have
(i) the same birthday?
(ii) different birthdays?
(iii) their birthday on the same weekday?