The average age of 40 students of a class is 15 years. When 10 new students are admitted, the average is increased by 0.2 years. The average age of new students is :

a. 15.2 yrs
b. 16 yrs
c. 16.2 yrs
d. 16.4 yrs

• Total Student -year for 40 students =40*15=600.
  
  when 10 new students were admitted the avg. increased by 0 .2 or becomes 15.2 years.
  
  Therefor new Student-year for 50 students=15.2*50=760.
  
  Student-year for 40 students 600 & for 50 students its 760, difference = 160.
  
  hence we can say that 160 student-years were added, which is of 10 student.
  
  Hence the average for 10 new students = 160/10 or 16 years .
  Option B is correct Which is 16 Years.
• 7 years agoHelpfull: Yes(1) No(0)
• let x be the age of total student and y be the total age of new 10 students now
  given x/40=15 , x=600
  now (600+y)/50=15.2
  y=160
  average of 10 students =160/10=16
• 6 years agoHelpfull: Yes(1) No(0)