If odds against solving a question by three students are 2:1, 5:2, and 5:3, respectively, then probability that the question is solved only by one student is a.`31//56` b. `24//56` c. `25//56` d. none of these

A problem is given to three students A,B,C then probability of solving is 0.6,0.5 and 0.7 respectively. What is the probability that is solved:

A four figure number is formed of the figures 1, 2, 3, 5 with no repetitions. The probability that the number is divisible by 5 is a. 3//4 b. 1//4 c. 1//8 d. none of these

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 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 2//7 b. 12//49 c. 32//343 d. none of these

For a question on probability the student's answer was 3/2 . The teacher told that the answer was wrong. Why ?

A problem in mathematics is given to three students A ,B ,C and their respective probability of solving the problem is 1/2, 1/3 and 1/4. Probability that the problem is solved is a. 3//4 b. 1//2 c. 2//3 d. 1//3

A problem in Mathematics is given to three students whose chances of solving it are 1/3, 1/4, and 1/5 (i) What is the probability that the problem is solved ? (ii) What is the probability that exactly one of them will solve it ?

The number of different seven-digit numbers that can be written using only the three digits 1, 2, and 3 with the condition that the digit 2 occurs twice in each number is a. 2P_5 2^5 b. 7C_2 2^5 c. 7C_2 5^2 d. none of these

A student appears for tests I, II and III. The student is considered successful if he passes in tests I, II or I, III or all the three. The probabilities of the Student passing in tests II and III are m, n and 1/2 respectively. If the probability of the student to be successful is 1/2 , then which one of the following is correct? (a) m (1+n)=1 (B) n (1+m) =1 (C) m=1 (D) mn=1