80% passed in maths,70% passed in science,65% passed in both?12 students failed in both subjects.how many students passed in both subjects?

• % of student passed in at least one subject=(80+75-65)%;
  =85%
  hence %of student failed in both=(100-85)%
  now
  15%of X=12 (let X be the total no of student)
  X=80;
  no of student passed in both subject=65% of 80;
  =52
  ans: 52
• 9 years agoHelpfull: Yes(1) No(0)
• let total students = x;
  
  passed in maths = 80x/100 = n(m);
  passed in science = 70x/100 = n(s);
  passed in both = 65x/100 = n(m^s);
  
  Hence, n(m U s) = n(m)+n(s)-n(m^s) = 85x/100;
  
  No. of students failed in both = (x - 85x/100) = 15x/100;
  
  Given, 15x/100 = 12;
  So, x = 80;
  
  Thus, no. of students passed in both = 65% of 80 = 52. (Ans)
• 9 years agoHelpfull: Yes(1) No(0)
• 60
  
  15%-12
  
• 9 years agoHelpfull: Yes(0) No(0)