The average age of a group of 12 students is 20years. If 4 more students join the group, the average age increases by 1 year. The average age of the new students is

A. 24

B. 26

C. 23

D. 22

• total age of 12 std=20*12
  total age of 16 std=21*16
  total age of 4 std=(21*16)-20*12=96
  avg of 4 std =(96)/4=24
• 12 years agoHelpfull: Yes(17) No(0)
• Total age of 12 students=12*20=240
  Total age of 4 students =4x(assuming the average age of 4 students)
  Hence the equation=240+4x=16*21=336
  solving the equation we get x=24
  So, average age of the new students =24
• 13 years agoHelpfull: Yes(7) No(0)
• sum of age of all 12 student=12*20=240
  
  average increased is 20+1=21 for new strenght 12+4=16
  
  then sum of age of new strenght with new average is 16*21=336
  
  total age of 4 new student=336-240=96
  
  then average age of 4 new students=96/4=24
  
  
• 11 years agoHelpfull: Yes(4) No(0)
• 8year*2=16
  45+35=80
  (80+16=96 so 96/2=48
  48 is wrong answer.....)
  because here 2years is increasing....
  so we have to subtract 16 from 80=64
  so average of 2 ladies is=64/2=32 is the answer.
• 10 years agoHelpfull: Yes(2) No(3)
• total age of 12 students=12*20=240
  If 4 more students join then 12+4=16,average age increases by 1 i.e)21
  so total age of 16 students=16*21=336
  total age of 4 students=336-240=96
  Average age of 4 students=96/4=24
  Answer is:24
• 10 years agoHelpfull: Yes(2) No(0)
• 4 members avg is = 20 + 16/4
  =20 + 4 = 24
• 8 years agoHelpfull: Yes(2) No(0)
• option D is correct(use rule of aligation)
  
• 10 years agoHelpfull: Yes(0) No(1)
• Correct Answer is 24 years.
• 9 years agoHelpfull: Yes(0) No(0)
• 12*20=240
  16*21=336
  336-240=94
  94/4=23.5
  ans is 24
• 9 years agoHelpfull: Yes(0) No(0)
• 4(x-20)/16=1
  x=24
• 9 years agoHelpfull: Yes(0) No(0)
• 12*20=240
  (12+4)*21=336
  336-240=96
  96/4=24ans
• 9 years agoHelpfull: Yes(0) No(0)
• Option A
  Total age before adding students=20*12=240
  Total age after adding students=21*16=336
  Total age of 4 students=336-240=96
  Average age=96/4=24
• 8 years agoHelpfull: Yes(0) No(0)
• ans is 24
• 8 years agoHelpfull: Yes(0) No(0)
• newly added students age sum = 21(16)-20(12)=96
  so avg of students newly added is 6/4 =24
  so Option B
• 7 years agoHelpfull: Yes(0) No(0)
• x/12=20
  x=240
  (x+y)/16=21
  x+y=336
  y=96
  y/4=24
• 6 years agoHelpfull: Yes(0) No(0)
• ewrsfsd
  al age of 16 std=21*16
  total age of 4 std=(21*16)-20*12=96
  avg of 4 std =(96)/4=24
• 6 years agoHelpfull: Yes(0) No(0)
• 12 Student Average Age = 20 Yrs,
  4 Students Added --> New Average Age = 21 Yrs,
  So, Every Student Age now 21 Yrs,
  =12/4
  =3 Yrs
  New Student Age is =21+3 Yrs = 24 Yrs
• 4 years agoHelpfull: Yes(0) No(0)