Out of the students who appeared in examination 80% passed in physics ,75% passed in literatureand 5% failed in both subject. If 300 them had passed in both subject ,how many students had appeared in the examination find by using a Venn diagram.(i am just a little confused)
In an examination, 70% of the candidates passed in English, 80% passed in mathematics, and 10% failed in both subjects. If 144 candidates passed in both, what is the total number of students? Let the total no of students be 100x
No of students failed =10*100x /100 = 10x
Thus , no of students passed = 100x - 10x = 90x
No of students passed in english = 7* 100x /100 =70x
No of students passed in maths = 8*100x / 100 =80x
Therefore no of students who passed in both = (80x + 70x) - 90x = 60 x
{{ Draw a venn diagram to understand this point ,
Or you could think like this:- when we add no of students passing in m and e individually ,we are counting those students who passed in both twice ,
Thus total students passed will be sum of no of students passed in maths and english individually - those who passed both.
