10 years ago Neha's mother was 4 times older than Neha. After 10 years Neha's mother will be twice Neha's age. How old is Neha now?

a) 10 years
b) 15 years
c) 17 years
d) 20 years
e) 23 years

• 20 years is correct
  Let us assume m = mother and n = neha
  m-10 = 4(n-10) => 4n-m = 30 this is equation 1
  m+10 = 2(n+10 => -2n+m = 10 this is equation 2
  By equations 1 and 2
  n=20
  n means Neha age = 20 years
• 8 years agoHelpfull: Yes(6) No(4)
• Let the age of Mother and Neha 10 years ago be 4x, x
  After 10 year
  Mother's age = 4x+10+10
  Neha's age=x+10+10
  4x+10+10=2(x+10+10)
  x=10
  Therefore, Neha's age=x+10=20yrs
• 8 years agoHelpfull: Yes(2) No(0)