. The average marks obtained by some students in an examination is 54. If 20% of the students got a mean score of 90 marks and the 30% of the students got a mean score of 20. Find the average marks of the remaining students.

• 60
  If total students are x
  and average of remaining students is y, then
  54x= 0.2x*90 +0.3x*20+0.5x*y
  54= 18+6+0.5y
  0.5y=30
  y=60
• 11 years agoHelpfull: Yes(3) No(0)
• Assume that there are total 100 students... Now according to question..
  20% of students means 20 students ( i.e 20% of 100),, thus sum of marks of 20 students= 20*90=1800
  similarly,
  sum of marks of 30 students=30*20=600
  now remaining=100-20+30=50 students
  let 50 students mean be x.thus sum of marks of 50 student = 50x.
  now applying the formula of average
  54= (1800+600+50x)/100 ..... we divided by 100 as we have assumed the total students to be 100.
  thus ans in 60
• 7 years agoHelpfull: Yes(1) No(0)