Question

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.

Answer 1

300/10% of students because 10%is only students who are fail.

Answer 2

Solution :-

Given -

50 % students passed in Mathematics

70 % students passed in science.

10 % of the total students failed in both subjects and 300 students passed in at least one subject.

Let x be the total number of students.

Total students = 100 %

Passed students = 100 - 10 (failed in both subjects)

= 90

Total passed students in at least one subject = (50 + 70) - 90  

= 30 %

So, 30 % of the total students passed in at least one subject.

⇒ (x*30)/100 = 300

⇒ 30x = 100*300

⇒ 30x = 30000

⇒ x = 30000/30

x = 1000

Total 1000 students appeared in the examination.