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 both the subjects. Find the total number of students who appeared in the examination, if they took examination in only two subjects.​

Answer 1

Complete step-by-step solution:

Given that,

50%50% of students are passed in Mathematics, then the percentage of failed students is 100%−50%=50%100%−50%=50%

70%70% of students are passed in Science, then the percentage of failed students is failed

Pf=50%+30%−10%=70%Pf=50%+30%−10%=70%

Now the total percentage of passed students is given by

Pp=100%−70%=30%Pp=100%−70%=30%

Let us assume the total number of students in the class as xx. Then the number of passed is

Np=x×30100=0.3xNp=x×30100=0.3x

But given that the number of passed students is 300300, then

0.3x=300⇒x=3000.3=10000.3x=300⇒x=3000.3=1000

So, the total number of students in the class is 1000.

Thank you