Ex.4.4 Q4 Simple-Equations Solution - NCERT Maths Class 7

Go back to  'Ex.4.4'


Solve the following riddle:

I am a number, 

Tell my identity!

Take me seven times over 

And add a fifty!

To reach a triple century 

You still need forty!

 Video Solution
Simple Equations
Ex 4.4 | Question 4

Text Solution

What is Known?

A riddle.

What is unknown?

The number in the riddle.


Use the given information to make an equation with unknown number as a variable. Solve the equation to get value of the number.


Let the number be \( x\).

According to question,

\[\begin{align}7x + 50 + 40 &= 300\\7x &= 300 - 90\\7x &= 210\\x = \frac{{210}}{7}&= 30\end{align}\]

Therefore, the number is \(30\)

Learn from the best math teachers and top your exams

  • Live one on one classroom and doubt clearing
  • Practice worksheets in and after class for conceptual clarity
  • Personalized curriculum to keep up with school