The average marks of 14 students was calculated as 71. But, it was discovered later that the marks of one student was taken as 42 instead of 56 and the marks of another student was wrongly taken as 74 while it was actually 32. If these corrections are now made then what is the average of the 14 students?
(a)67(b)68(c)69(d)71

• ans :(c) 69
  total marks =14*71 = 994
  marks with out that two studnts = 994-42-74 = 878
  total marks ith corrections = 878+56+32 = 966
  the average marks = 966/14 =69
• 13 years agoHelpfull: Yes(2) No(0)
• ans is 69
  avg of 14 std =71 in which we took42 instead of 56 and we took 74 instead of 32 so once we we took (56-42)=14 less than actual value and (74-32)=42 more than actual value so in total we used 42-14 =28 more than actual value
  i.e. we increamented avg by 28/14=2 so actual avg is 71-2=69
  actual avg is 69.
  
• 13 years agoHelpfull: Yes(1) No(0)
• let total marks be a.
  a/14=71,a=994
  {994-(42+74)+(56+32)}/14=69ans
• 13 years agoHelpfull: Yes(1) No(0)
• 14*71-42-74+56+32=966
  966/14=69
• 8 years agoHelpfull: Yes(0) No(0)
• shortcut method:-
  difference between 56 and 42=56-42=14
  14/no.of students=14/14=1
  71+1=72
  now,difference between 74 and 32=42
  42/14=3
  72-3=69
• 7 years agoHelpfull: Yes(0) No(0)