Maths
posted by Neeraj Bhanot .
Among the examinees in an examination 30%, 35% and 45% failed in Statistics, in Mathematics, and in at least one of the subjects respectively. An examinee is selected at random. Find the probabilities that
a. He failed in Mathematics only
b. He passed in Statistics, if it is known that he has failed in Mathematics

P(S and M) = P(S) + P(M)  P(S or M)
= .3 + .35  .45
= .2
You could now make a Venn Diagram with two overlapping circles called S and M
Enter .2 into the overlap ( the P(S and M) )
since S must be .3 and .2 is already accounted for, the part of ONLY S would be .1
in the same way the part of M only would be .15
Respond to this Question
Similar Questions

IGNOU probability
Among the examinees in an examination 30%, 35% and 45% failed in Statistics, in Mathematics, and in at least one of the subjects respectively. An examinee is selected at random. Find the probabilities that a. He failed in Mathematics … 
statistics
among the exames in the examination 30%, 35% & 45% failed in statistics, in maths, & in atleast one of the subjects respectively. one student is selected at random. find the probability that: (a)he has failed in maths, (b)he passed … 
probability
among the exames in the examination 30%, 35% & 45% failed in statistics, in maths, & in atleast one of the subjects respectively. one student is selected at random. find the probability that: (a)he has failed in maths, (b)he passed … 
statistics
Among the 500 first year students of college, 270 students study computer science, 345 students study mathematics, and 175 students study both computer science and mathematics. If one student is selected at random, find the probability … 
mathematics
1. In an examination conducted for 80 candidates, those who passed in mathematics were 17 more than those who passed science and 9 failed both subjects.14 candidates passed both subjects. I. Draw a venn diagram to illustrate this information … 
math
In a group of 105 students, 70 students passed Mathematics, 60 students passed History and 45 students passed Geography; 30 students passed Mathematics and History, 35 students passed History and Geography, 25 passed Mathematics and … 
Math
In a group of 105 students, 70 students passed Mathematics, 60 students passed History and 45 students passed Geography; 30 students passed Mathematics and History, 35 students passed History and Geography, 25 passed Mathematics and … 
mathematical methods for economics
in a class of 300 students,they were given mathematics test in three subjects namely,economics,statistics and mathematics,90 students failed in economics,100 failed in statistics,96 failed in mathematics,60 failed in economics and … 
Business mathematics
In an examination of certain number of candidates 18 passed mathematics, 17 passed physics, 11 passed both mathematics and physics, 1 failed both subjects. Find the number of candidates that passed. i. Mathematics only. ii. Physics … 
Math
In an examination of a certain class, at least 70% of the students failed in Physics, at least 72% failed in Chemistry, at least 80% failed in Mathematics and at least 85% failed in English. How many at lest must have failed in all …