A box contains 90 discs. Which are numbered from 1 to 90. If one disc is drawn at randow from the box. Find the probability that is bears a perfect square number.

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 a two - digit number .

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 a number divisible by 5.

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-digit number (ii) a perfect square number (iii) a number divisible by 5.

A box contains 90 dices which are numbered from 1 to 90. If one dise is drawn at random from the box, find the probability that it bears i) two digit number ii) a perfect square number.

A box contains 90 discs, numbered from 1 to 90. If one disc is drawn at random from the box, the probability that it bears a prime-number less than 23, is:

A box contains 19 balls bearing numbers 1,2,3, . .,19. a ball is drawn at random from the box. Find the probability that the number on the ball is i] a prime number ii] divisible by 3 or 5. iii] neither divisible by 5 nor by 10 iv] an even number.

A bag has cards numbered 2 to 90. a card is drawn at random from the bag. Find the probability that it bears (i) a two-digit number (ii) a number which is a perfect square.

A box contains 12 balls out of which x are black. If one ball is drawn at random from the box, what is the probablity that it will be a black ball? If 6 more black balls are put in the box, the probability of drawing a black ball is now double of what it was before. find x.

A box contains 12 balls out of which x are black. If one ball is dran at random from the box, what is the probability that it will be a black ball? If 6 more black balls are put in the box, the probability of drawing a black ball is now double of what it was before. Find x.