One of 10 keys open the door. If we try the keys one after another, then find the following:
(i) the probability that the door is opened on the first attempt.
(ii) the probability that the door is opened on the second attempt.
(iii) the probability that the door is opened on the 10th attempt.

One is asked to say a two-digit number i) What is the probability of both digits being the same? ii) What is the probability of the first digit being larger? iii) What is thè probability of the first digit being smallẹr?

One bag contains 5 white and 3 black balls. Another bag contains 7 white and 8 black balls.A ball is transferred from the first bag to the second and then a ball is drawn from the second. Find the probability that the ball drawn from the second bag is white

An urn contains 9 red, 7 white and 4 black balls. If two balls are drawn at random, find the probability. that, (i) both the balls are red (ii) one ball is white, (iii) the balls are of the saime colour (iv) one is white and other red.

A bag contains 5 white balls and 3 black balls. Two balls are drawn at random one after the other without replacement. Find the probability that the first draw gives a white ball and the second draw gives a black ball

The handle of a door is always found at one edge of the door which is located at a maximum possible distance away from hinges. In which direction will the torque act while the door opens inside the room?

In class 10 ~A , there are 30 bóys and 20 girls ln 10 ~B , there are 15 boys and 25 girls One student is to be selected from each class i) What is the probability of both being girls? ii) What is the probability of both being boys? iii) What is the probability of one boy and one girl? iv) What is the probability of atleast one boy?

There are 3 red balls and 7 green balls in a bag, 8 red and 7 green balls in another. i) Whạt is the probability of getting a red ball from the first bag? ii) From the second bag? iii) If all the balls are put in a single bag, what is the probability of getting a red ball from it?

A box contains 10 black beads and 15 white beads Another box contains 11 black beads and 17 white beads Without looking, a bead is drawn from each box i) What is the probability of getting a black bead from the first box? ii) What is the probability of getting a black bead from the second box? iii) Which box give more chance to get a white bead Why?

One card is drawn from a pack of 52 cards, each of the 52 cards being equally likely to be drawn. Find the probability that the card drawn is: (i) an ace, (ii) red, (iii) either red or king, (iv) red and a king.