The probability of selecting a rotten apple randomly from a heap of 900 apples is 0.18. What is the number of rotten apples in the heap?

A bag contains 15 white and some black balls. If the probability of drawing a black ball from the bag is thrice that of drawing a white ball, find the number of black balls in the bag.

Two different dice are thrown together. Find the probability that the numbers obtained have

(i) even sum, and

(ii) even product

354.

Two dice are thrown together. The probability of getting the same number on both dice is:

• $\frac{1}{2}$

• $\frac{1}{3}$

• $\frac{1}{6}$

• $\frac{1}{12}$

A number is selected at random from first 50 natural numbers. Find the probability that it is a multiple of 3 and 4.

A 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) the queen of diamonds.

Describe the sample space for the following experiment.
A coin is tossed three times.

Describe the sample space for the following experiment.
A die is thrown two times.

Describe the sample space for the following experiment.
A coin is tossed four times.

Describe the sample space for the following experiment.
A coin is tossed once.