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

Go back to 'Ex.4.4'

## Question

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!

## Text Solution

**What is Known?**

A riddle.

**What is unknown?**

The number in the riddle.

**Reasoning:**

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

**Steps:**

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 \(30\)