Question

Arpita’s present age is three times Shilpa’s age. If Shilpa’s age three years ago was $x$. Then what will be the present age of Arpita?

Answer 1

Hint: In order to solve these types of questions, we have to assume that the current age to be as $x$, then the age $k$ years ago will become $x - k$ years. Now in the present question assume that the present age of Shilpa to be as $n$ and do the calculations as per given conditions.

Complete step-by-step solution:
Given in the question that Arpita’s present age is three times Shilpa’s age. If Shilpa’s age three years ago was $n$, and we have to determine the present age of Arpita.
Let Shilpa’s present age be $n$ years,
Then it is given that the present age of Arpita is three times of Shilpa,
So Arpita’s present age will be $3n$ years,
Now from the given data,
Three years age Shilpa’s age is $x$ years,
So, the present age of Shilpa’s age is $x + 3$ years.
From the data we got from the question,
$\therefore x + 3 = n$,
  Arpita’s present age=$3n$ years,
  Arpita’s present age$ = 3\left( {x + 3} \right)$ years.
$\therefore $ Arpita’s present age$ = 3x + 9$

The present age of Arpita is $3x + 9$ years.

Note: When to and where to do basic Addition, subtraction, multiplication and division needed to be clear to reach the correct answer, and the values given in the questions should be placed correctly without getting confused in an equation by assuming variable to the values that are to be calculated. When we form the equation, solve the equation to get the required answer. We need two equations if we have 2 unknown variables. We will need only one equation when we have only 1 unknown variable.