Two persons A and B agree to meet at a place between 11 to 12 noon. The first one to arrive waits for 20 minutes and then leave. if the time of their arrival be independent and at random, then the probability that A and B meet is:

The first 12 letters of English alphabet are written down at random in a row. The probability that there exactly 4 letters between A and B , is

In the box there are a white and b black balls. Two persons A and B takes ball one after the other and each time ball is placed back in box. Person A starts the game. If white ball is obtained then person A wins the game probability of winning game by person A is double then the winning probability of person B. Then a : b = .........

Form the pair of linear equations in the following problems and find their solutions (if they exist) by any algebraic method: Places A and B are 100 km apart on a highway. One car starts from A and another from B at the same time. If the cars travel in the same direction at different speeds, they meet in 5 hours. If they travel towards each other, they meet in 1 hour. What are the speeds of the two cars?

A chess game between two grandmasters X and Y is won by whoever first wins a total of two games. X's chances of winning or loosing any perticular game are a, b and c, respectively. The games are independent and a+b+c=1. The probability that X wins the match after (n+1)th game (nge1) , is

A chess game between two grandmasters X and Y is won by whoever first wins a total of two games. X's chances of winning or loosing any perticular game are a, b and c, respectively. The games are independent and a+b+c=1. The probability that Y wins the match after the 4th game, is

A chess game between two grandmasters X and Y is won by whoever first wins a total of two games. X's chances of winning or losing or draw any particular game are a, b and c, respectively. The games are independent and a+b+c=1. The probability that X wins the match, is

A and B are two independent witnesses (i.e., there is no collision between them) in a case. The probability that A will speak the truth is x and the probability that B will speak the truth is y. A and B agree in a certain statement. Show that the probability that the statement is true is (xy)/(1-x-y+2xy) .

A manufacturer has three machine operators A, B and C. The first operator A produces 1% defective items, where as the other two operators B and C produce 5% and 7% defective items respectively. A is on the job for 50% of the time, B is on the job for 30% of the time and C is on the job for 20% of the time. A defective item is produced, what is the probability that it was produced by A?

Places A and B are 100 km apart from each other on a highway. A car starts from A and another from B at the same time. If they move in the same direction, they meet in 10 hours, but if they move towards each other they meet in 1 hour 40 minutes. Find the speeds of the cars.

A man wishes to throw two darts one by one at the target at B with same speed so that they arrive at the same time. Mark the CORRECT statements about the two projections.