Question

# Write as percentage for the number $4\dfrac{4}{{20}}$${\text{A}}{\text{. 84% }} \\ {\text{B}}{\text{. 420% }} \\ {\text{C}}{\text{. 8}}{\text{.4% }} \\ {\text{D}}{\text{. 42% }} \\$

Hint:- If you have to find the percentage of a number, first convert it in fractional form and simply multiply it by $100$ you will get a percentage of that number. Or you may change it in decimal form and multiply by $100$ you will get a percentage.
We have to find percentage of $4\dfrac{4}{{20}}$
We can write it as $4\dfrac{4}{{20}} = \dfrac{{84}}{{20}}$
$\left( {4\dfrac{4}{{20}} = \dfrac{{20 \times 4 + 4}}{{20}}} \right)$that is denominator multiply by outer number and add numerator divide by denominator.
For finding percentage we will multiply by $100$, we get
$\dfrac{{84}}{{20}} \times 100 = 420\%$
Hence option ${\text{B}}$is the correct option.
Note:- Whenever you get this type of percentage question, the key concept of solving is simply convert it into fractional form or decimal form whichever is easy in that question do that and multiply by $100$you will get a percentage of that question. If the question is already in decimal or fractional then simply multiply by $100$and get the percentage of that number.