A father is three times as old as his son. After fifteen years the father will be twice as old as his son's age at that time. Hence the father's present age is
A. 36 B. 42 C. 45 D. 48 E. None of the above

• Let the son's age be x, then father's age 3x
  After 15 years:
  Father's age: 3x+15
  Son's age:x+15
  Now the equation is:2(x+15)=3x+15
  Solving we get x=15
  Hence, father's present is 45(option C)
• 12 years agoHelpfull: Yes(31) No(1)
• Let son's age = x
  father's age =3x
  ..
  After 15 years
  son's age = x+15
  father's age = 3 x+15
  ..
  3 x+15=2(x+15)
  3 x+15=2 x+30
  x=15.. son's age now
  Father's age now = 3 x = 45
• 8 years agoHelpfull: Yes(0) No(0)
• let father age=x and son age=x then x=3x,
  after 15 years father age is twice i.e., 2(x+15)=3x+15
  2x+30=3x+15
  x=15 then father age is 3x=3*5=45.
• 8 years agoHelpfull: Yes(0) No(0)
• father = 3x Son = x;
  after 15 years .. father = 3x+15 and son = x+15...Father will be twice son's age therefore ..(3x+15)=2(x+15) therefore x=15 and father age = 45
• 8 years agoHelpfull: Yes(0) No(0)
• Consider the present age of son = x
  Then His father's present age=3x
  According to question,
  3x+15=2(x+15)
  3x-2x=30-15
  x=15
  His father's present age= 3x
  =3*15
  =45
  Answer is C. 45
• 8 years agoHelpfull: Yes(0) No(0)
• Lets present age of father be 'x' and sons age be 'y'.
  at present,
  x=3y;
  after 15 years,
  x+15=2(y+15),
  by solving and substituting,we get
  x=45//option C
• 5 years agoHelpfull: Yes(0) No(0)
• 45
  3s=f
  2(s+15)=f+15
• 5 years agoHelpfull: Yes(0) No(0)
• 3:1
  After 15y
  2:1
  Increased part (3p-2p)=15
  1p=15
  3p=45
• 4 years agoHelpfull: Yes(0) No(0)
• son present age is = x
  then father present age is = 3x
  
  after 15 years son and father age is->
  x+15 = 3x+15
  now father will be twice as old as his son than 2(x+15) = 3x+15
  after solving x = 15
  father present age is = 3x
  =3 x 15
  = 45
• 4 years agoHelpfull: Yes(0) No(0)
• ans = c
  f=3*s ------------(i)
  after 15 years father=f+15
  and son= s+15
  now according question= > f+15=2(s+15)
  => f+15=2s+30
  =>f-2s=15---------------(ii)
  put (i) in (ii)
  3s-2s=15
  s=15
  put the value of s in (i)
  f=3*s
  f=3*15
  f=45
• 3 years agoHelpfull: Yes(0) No(0)