The ages of a mother and daughter are 36 years and 12 years, respectively. In how many years will the mother be twice the age of the daughter?
12 years
Let the required number of years be \(x\). After \(x\) years the mother's age is \(36 + x\) and the daughter's age is \(12 + x\).
The condition is that the mother is twice as old as the daughter: \(36 + x = 2(12 + x)\).
Expanding the right side gives \(36 + x = 24 + 2x\).
Rearranging, \(36 - 24 = 2x - x\), so \(x = 12\).
Hence, after 12 years the mother will be twice the daughter's age.
Three years ago, the average age of a family of six members was 19 years. Since then, a boy has been born, and the average age of the family is the same today as it was three years ago. What is the age of the boy?
Amita is 2 years older than her friend Amrita. Amita's father is twice as old as Amita, and Amrita is twice as old as her sister. The ages of Amita's father and Amrita's sister differ by 43 years. The sum of the ages (in years) of Amita and Amrita is: