If the papers of 4 students can be checked by any one of the 7 teachers, then the probability that all the 4 papers are checked by exactly 2 teachers is a.`2//7` b. `12//49` c. `32//343` d. none of these

If the papers of 4 students randomly distributed for checking among 7 teacher, then the probability that all the 4 papers are checked by exactly 2 teachers is n/m where n, m are natural number and HCF(n,m)=1 . Then number of positive divisiors of (n+m) is

* In a race,the probability of A to win the race is (1)/(7) and of B is (1)/(4). Find the probability that any one of them win the race

The probability that a certain kind of component will survive a check test is 0.6 Find the probability that exactly 2 of the next 4 rested componentws suvive.

A student took five papers in ail examination, where hill marl were same on each paper. Her marks in these papers were in the proportion of 6:7:8:9:10. In all these papers together, the candidate obtained 60% of the total marks. Then the number of papers in which she got more than 50% marks is 2 b. 3 c. 4 d. 5 e. none of these

In a class of 65 students and 4 teachers,each student got sweets that are 20% of the total number of students and each teacher got sweets that are 40% of the total number of students.How many sweets are there? 104 b.84 c.949 d.897 e.none of these