EX.2.2 Q12 Linear Equations in One Variable Solutions - NCERT Maths Class 8


Question

Fifteen years from now Ravi’s age will be four times his present age. What is Ravi’s present age?

 Video Solution
Linear Equations
Ex 2.2 | Question 12

Text Solution

What is known?

Fifteen years from now Ravi’s age will be four times his present age.

What is unknown?

Ravi’s present age

Reasoning:

Assume Ravi’s age to be a variable. Use the first and second condition to express his age after \(15\) years in the form of a linear equation.

Steps:

Let the present age of Ravi be \(x\) years.

\(15\) years from now, Ravi’s age will be \(4\) times his present age

\[\begin{align}x + 15 &= 4x\\x - 4x &=  - 15\\ - 3x &=  - 15\\x &= \frac{{ - 15}}{{ - 3}}\\x &= 5\end{align}\]

\(\therefore\) Ravi’s present age is \(5\) years

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