ASSIGNMENT 2

PROBABILITY: CLASS X

1.   Three coins are tossed once. Find probability of:

 (a) 3 heads

 (b) exactly 2 heads

(c) at least 2 heads

 (d) at most 2 heads

 (e) no tails

 (f) head and tail appear alternatively

(g) at least one head and one tail

2. A coin is tossed successively three times. Find probability of getting exactly one head.    

    3. Two dice are thrown simultaneously. Find:

          (a) P(an odd number as a sum)

    (b) P(sum as a prime number)

    (c) P(a doublet of odd numbers)

    (d) P(a total of at least 9)

    (e) P( a multiple of 2 on one die and a multiple of 3 on other die)

    (f) P(a doublet)

   (g) P(a multiple of 2 as sum)

   (h) P(getting the sum 9)

   (i) P(getting a sum greater than 12)

   (j) P( a prime number on each die)

   (k) P( a multiple of 5 as a sum)

4.  Find the probability that a leap year at random contains 53 Sundays.

5. A bag contains 100 identical tokens, on which numbers 1 to 100 are marked. A token is drawn at random. What is the probability that the number on the token is:

 (a) an even number

 (b) an odd number

 (c) a multiple of 3

 (d) a multiple of 5

 (e) a multiple of 3 and 5

 (f) a number less than 20

 (g) a number greater than 70

 (h) a perfect square number

 (i) a prime number less than 20.

6. Two dice are rolled once what is the probability of getting a doublet?

7. A die is rolled once. What is the probability of getting a prime number?

8. A bank A.T.M. has notes of denomination 100, 500 and 1000 in equal numbers.  

   What is the probability of getting a note of Rs. 1000.

9. What is the probability of getting a number greater than 6 in a single throw of a

    die.

10. It is known that in a box of 600 screws, 42 screws are defective. One screw is taken out at random from this box. Find the probability that it is not defective.

11.  A box contains card numbered from 2 to 101. One card is drawn at random.  What is the probability of getting a number which is a perfect square.