A can solve 90% of the problems given in a book and B can solve 70%. What is the probability that  at least one of them will solve the problem, selected at random from the book?

One boy can solve 60% of the problem in a book and another can solve 80% . The probability that at least one of the two can solve a problem chosen at random from the book is .

Given the probability that A can solve a problem is 2/3 and the probability that B can solve the same problem is 3/5. Find the probability that none of the two will be able to solve the problem.

How many times must a man toss a fair com so that the probability of having at least one head is more than 90%?

Suppose that 90% of people are right-handed. What is the probability that at most 6 of a random sample of 10 people are right-handed?

Suppose that 90% of people are right-handed. What is the probability that at most 6 of a random sample of 10 people are right-handed?

Suppose that 90% of people are right-handed. What is the probability that at most 6 of a random sample of 10 people are right-handed?

Three persons, Aman, Bipin and Mohan attempt a Mathematics problem independently. The odds in favour of Aman and Mohan solving the problem are 3:2 and 4:1 respectively and the odds against Bipin solving the problem are 2 :1 Find (i) The probability that all the three will solve the problem (ii) The probability that problem will be solved

The probability that A can solve a problem is 2//3 and B can solve it is 3//4 . If both attempt the problem, what is the probability that the problem gets solved ?

A problem in mathematics is given to 3 students whose chances of solving it are 1/2; 1/3; 1/4 . What is the probability that the problem is solved?

A computer solved several problems in succession. The time it took to solve each successive problem was the same number of times smaller than the time it took to solve the preceding problem. How many problems were suggested to the computer if it spent 63.5 min to solve all the problems except for the first, 127 min to solve all the problems except for the last one, and 31.5 min to solve all the problems except for the first two?