Question

What is the value of $\dfrac{4}{5}\%$ of 500 ?

Answer 1

Hint: To calculate $\dfrac{4}{5}\%$ of 500, we should use the definition of percentage, i.e., specific kind of values per 100 values. Further, we will need to use unitary method technique to find the required value. From a set of 100 values, we are interested in $\dfrac{4}{5}$ of them. So, from 500 values, we will need $\dfrac{4}{500}\times 500$ . This will give us the required answer.

Complete step-by-step solution:
We know that the word ‘percentage’ is made up of a combination of 2 words, ‘per’, which means ‘for every’, and ‘cent’, which is equivalent to the number 100. Thus, percentage refers to the number of specific values per hundred values.
In our problem, we need to find $\dfrac{4}{5}\%$ of 500.
According to the definition of percentage, $\dfrac{4}{5}\%$ means $\dfrac{4}{5}$ out of 100.
We can rephrase this information as,
From 100, we need = $\dfrac{4}{5}$
By using unitary method, we can say that
From 1, we need = $\dfrac{4}{500}$
And thus,
From 500, we need = \[\dfrac{4}{500}\times 500=4\]
Alternatively, we can use the direct formula to solve this problem.
We know that to find A% of B, we can write A% of B = $\dfrac{A}{100}\times B$
Now, if we use this formula to solve our problem, we get
$\dfrac{4}{5}\%$ of 500 = $\dfrac{\left( \dfrac{4}{5} \right)}{100}\times 500$.
Thus, $\dfrac{4}{5}\%$ of 500 = \[\dfrac{4}{500}\times 500=4\]
Hence, $\dfrac{4}{5}\%$ of 500 is 4.

Note: We must understand the concepts of unitary method to solve this problem. Alternatively, we may use the direct formula to solve this problem, which can be written as, A% of B = $\dfrac{A}{100}\times B$. We must take care not to write it as $\dfrac{\left( \dfrac{4}{5} \right)}{500}\times 100$ which will give a totally wrong answer.