Question

How old am I if 400 is reduced by 4 times my age is 80?

Answer 1

Hint: We are given a statement as ‘400 is reduced by 4 times my age is 80’. We have to solve this and find the age of the person. We will first let the age of the person as ‘x’ then we will change this statement into the algebraic expression. Once we get an algebraic expression we will learn about the degree and then find the exact solution to it.

Complete step by step answer:
We are given a statement as 400 reduces by 4 times my age is 80, we will start our solution by reducing this into algebraic expression.
To do so, we will understand that reduced mean difference, 4 times my age mean 4 multiplied by ‘m’ age and lastly it is used for ‘=’.
So, let the age of the person is ‘x’, then 400 reduced by 4 times my age is 80.
$\Rightarrow 400-4\times x=80$
So, we get equation as –
$400-40x=80$
So, as we can see that this equation has 1 variable and its helpful power is 1, so this equation can have at most 1 solution.
We will use algebra to solve.
We have $400-4x=80$
We subtract 400 on both sides –
So, $400-4x-400=80-400$
By simplifying, we get –
$-4x=-320$ (as $80-400=-320$ )
Now we divide both sides by -4.
So, $\dfrac{-4x}{-4}=\dfrac{-320}{-4}$
By simplifying, we get –
$x=80$

Hence the age of the person is $x=80$.

Note: Once we get the equation, we can also find the solution using the hit and trial method, in this way we put value of variable by assumption and check whether it is true or not, this way is little quick in simple equation for example $x+2=3$ but it gets difficult for the complex equations. We can also plot the graph and the point where it cuts the x-axis will be our solution.