In an examination 50% of the students passed in Mathematics and 70% of students
passed in Science while 10% students failed in both subjects. 300 students passed in
atleast one subject. Find the total number of students who appeared in the examination,
if they took examination in only two subjects.
Answers
Answered by
9
A = event that person passes in Maths
B = event that person passes in Science
P(A) = 0.5
P(B) = 0.7
P(A∪B) = probability that person passes in atleast one subject
1-P(A∪B) = probabiliy that person fails in both subjects = 0.1
P(A∪B) = 0.9 = 300/Total number of students
Total number of students = 300/0.9 ≈ 333
B = event that person passes in Science
P(A) = 0.5
P(B) = 0.7
P(A∪B) = probability that person passes in atleast one subject
1-P(A∪B) = probabiliy that person fails in both subjects = 0.1
P(A∪B) = 0.9 = 300/Total number of students
Total number of students = 300/0.9 ≈ 333
shanthidevi812:
Given
Answered by
24
P(a)=50/100,p(b)=70/100p(anb)=1-10/100=90/100
P(aorb)=70/100+50/100-90/100
300=30x/100=1000
No of students appeared is 1000
P(aorb)=70/100+50/100-90/100
300=30x/100=1000
No of students appeared is 1000
Attachments:
How can probability of people passing in both subjects, which is P(A intersection B), be more than the probability of passing in a single subject, either P(A) or P(B)? I think you have misinterpreted the question.
how did 90/100 please explain
how 9-10/100=90/100
please explain
Similar questions