The average age of 150 students in a class is 40% of the number of students in the class and the average age of a group of 50 students present in the class is 32yrs and the average age of another 50 students in the class is 36yrs. What is the average age of the remaining students in the class? A) 102 B) 118 C) 112 D) 108

1 Answer

Answer :

C)

150 students average 150×40/100=60 years

According to the question,

150×60=50×32+50×36+50×X

50×X=9000-1600-1800

50x=5600

X=112


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