 QUESTION

# Find the whole quantity if $5%$ of it is 600.

Hint: Assume that the whole quantity is ‘x’. Use the fact that $a%$ of ‘b’ has value $\dfrac{ab}{100}$. Write the linear equation in one variable in ‘x’ and simplify it by rearranging the terms to calculate the value of ‘x’ which satisfies the equation.

We have to find the whole quantity whose $5%$ is 600.
We will assume that the whole quantity is ‘x’. Thus, we know that $5%$ of ‘x’ is 600. We have to calculate the value of ‘x’.
We know that $a%$ of ‘b’ has the value $\dfrac{ab}{100}$.
Substituting $a=5,b=x$ in the above expression, $5%$ of ‘x’ is $=\dfrac{5x}{100}$.
But we know that $5%$ of ‘x’ is 600.
Thus, we have $\dfrac{5x}{100}=600$.
Simplifying the above expression by cutting out the like terms, we have $\dfrac{x}{20}=600$.
Cross multiplying the terms of the above equation, we have $x=20\times 600=12000$.
Hence, the whole quantity whose $5%$ is 600 is 12000.
Note: We can verify if the above calculations are correct or not by calculating the value of $5%$ of 12000 and checking if it equals 600 or not. A percentage is a number or a ratio that represents a fraction out of 100. It is often denoted using the percent sign %. It is a dimensionless number. It is used to express a proportionate part of a total. The percentage value is computed by multiplying the numerical ratio of two numbers by 100.