2. Questions Bank
  3. 8th Class
  4. Mathematics
  5. Linear Equations in One Variable

8th Class Mathematics Linear Equations in One Variable Question Bank Linear equations in One Variable

  • question_answer
    Two years ago, Mohit was three times as old as his son and two years hence, twice of his age will be equal to five times that of his son. Then the present age of Mohit is _____.

    A)  14 years

    B)         38 years         

    C)  32 years         

    D)         34 years         

    Correct Answer: B

    Solution :

    Let present age of Mohit be x years Two years ago, his age = (x - 2) years So, his son's age\[=\left( \frac{x-2}{3} \right)\] years So, present age of son\[=\left( \frac{x-2}{3}+2 \right)\]years After 2 years, son's age\[=\left( \frac{x-2}{3}+2+2 \right)\]years and that of Mohit\[=(x+2)\]years So, according to question, we have \[2(x+2)=5\left( \frac{x-2}{3}+2+2 \right)\] \[\Rightarrow 2x+4=\frac{5x-10}{3}+20\] \[\Rightarrow 2x-\left( \frac{5x-10}{3} \right)=20-4\] \[\Rightarrow \frac{6x-5x+10}{3}=16\Rightarrow x+10=48\] \[\Rightarrow x=48-10=38years\] \[\therefore \] Present age of Mohit = 38 years.


You need to login to perform this action.
You will be redirected in 3 sec spinner