Question

What is $90\%$ of $9$?

Answer 1

Hint: In the above question, we have been asked to calculate a given percentage of a given number. The given percentage value is equal to $90\%$ and the given number is equal to $9$. For calculating $90\%$ of nine, we must first convert the given percentage $90\%$, from percentage to the decimal form. For this, we need to replace the percentage sign by the multiplication of the number $90$ by the factor $\dfrac{1}{100}$ and then carry out the necessary division to convert the percentage into decimal. Then finally, we need to multiply the obtained decimal with the given number, which is equal to $9$, to finally obtain the required percentage.

Complete step by step answer:
According to the question, we have to calculate $90\%$ of $9$. For that, we need to convert the percentage $90\%$ into the decimal.
We know that the percentage symbol is equivalent to the multiplication by the factor $\dfrac{1}{100}$ so that the given percentage will become equal to
$\begin{align}
  & \Rightarrow 90\times \dfrac{1}{100} \\
 & \Rightarrow \dfrac{90}{100} \\
\end{align}$
On dividing the numerator by the denominator, we get
$\Rightarrow 0.9$
Now, for obtaining the required percentage, we have to multiply the decimal number obtained above with the given number, which is equal to $9$ to get
\[\Rightarrow 0.9\times 9\]
On solving the above multiplication, we finally get
\[\Rightarrow 8.1\]

Hence, we have calculated the given percentage to be equal to \[8.1\].

Note: The multiplication of the decimal number, which is obtained by converting the given percentage, is indicated by the term “of” written in the phrase $90\%$ of $9$. The term “of” indicates multiplication in mathematics. Also, do not make the mistake of adding a percentage sign after the final answer.