Question

43) In an examination, 80% of the
students passed in English, 85% in
Mathematics and 75% in both
English and Mathematics. If 40%
students failed in both the subject,
find the total number of students.
एक परीक्षा में, 80% छात्र अंग्रेजी में उत्तीर्ण हैं,
गणित में 85% और 75% दोनों (अंग्रेजी और
गणित में). अगर 40% छात्र दोनों विषय में
अनुतीर्ण है, कुल छात्रों की संख्या बताइये।​

Answer 1

Step-by-step explanation:

Let A and B represent the sets of students who passed in English and Mathematics respectively . Then number of students passed in one or both the subjects = nA∪B=nA+nB- nA⋂B=80% of x + 85% of x –75% of x =[80/100x+85/100x-75/100x]=90/100x=9/10x Students who failed in both the subjects = [x-9x/10]=x/10.