The probability that a teacher will conduct an unannounced test during any class meeting is `1/4` . If a student of the class is absent twice, then the probability for the student to miss at least one test is
(A) `3/16` (B) `6/16` (C) `1/16` (D) `7/16`

The probability that a teacher will give a surprise test during any class is 1/5. If a student is absent on two day what is the probability that he will miss atleast one test.

A coin is tossed 5xx.The probability that at least one head turns up,is (1)/(16) b.(2)/(16) c.(14)/(16) d.(15)/(16)

A college student has to appear for two examinations A and B. The probabilities that the student passes in A and B are 2/3 and 3/4 respectively. If it is known that the student passes at least one among the two examinations, then the probability that the student will pass both the examination is (A) 1/6 (B) 1/2 (C) 1/3 (D) 6/11

The probability that in a family of four children,there will be atleast one boj is (A) (1)/(16)(B)(3)/(16) (C) (13)/(16) (D) (14)/(16)

The probabilities of a student getting first class or second class or third class in an examination are (2)/(7) , (3)/(5) ,(1)/(10) respectively . The probability that the students fails is .

The probability of A hitting a target is (4)/(5) the probability of B hitting the target is (3)/(4) and the probability of C missing the target is (1)/(3) .What is the probability of the target being hit at least twice.

The mean score in a test of the 10 boys in a class was 15 while the overall mean of the 25 students in the class was 16.2. What was the mean score of the girls?

The mean score 1n a test of the 12 boys in a class was 16 while the overall mean of the 30 students in the class was 18.1. What was the mean score of the girls?