Question

What is $75\%\;$ of 40?

Answer 1

Hint: We need to find out $75\%\;$ of 40. Firstly, we start to solve the problem by expressing 70 percent in the form of a fraction. Then, we multiply the fraction with the number 40 to get the desired result.

Complete step by step answer:
Let the value of $75\%\;$ be $n$
We are asked to find out of n. We will be solving the given question by finding out the product of $75\%\;$ and 40.
A percentage is a value expressed as a fraction of a hundred or $\dfrac{1}{100}$ . It is denoted by the symbol ’$\%\;$’. The value expressed as a percentage does not have any dimension or unit of measurement.
For Example:
$\Rightarrow 2\%,3\%$
According to the question,
We are required to express $75\%\;$ in the form of a fraction.
$\Rightarrow 75\%$
The word percent means ‘per hundred’.
Dividing the given percentage with hundred, we get,
$\Rightarrow 75\times \dfrac{1}{100}$
$\Rightarrow \dfrac{75}{100}$
Expressing the above fraction as the product of factors, we get,
$\Rightarrow \dfrac{\left( 25\times 3 \right)}{\left( 25\times 4 \right)}$
Cancelling the common factors, we get,
$\Rightarrow \dfrac{3}{4}$
$\therefore 75\%=\dfrac{3}{4}$
Now,
We need to multiply the value of $75\%\;$ with the number 40 to get the value of $n$ .
Writing the same, we get,
$\Rightarrow n=\dfrac{3}{4}\times 40$
Cancelling out the common factors, we get,
$\Rightarrow n=3\times 10$
$\therefore n=30$

Therefore, the value of $75\%\;$ of 40 is 30.

Note: The given question can be solved alternatively as follows,
The output value is 40.
The value of $75\%\;$ of 40 be $x$ .
Forming simple equations for the above sentences, we get,
$\Rightarrow 40=100\%$
$\Rightarrow x=75\%$
Dividing the above simple equations, we get,
$\Rightarrow \dfrac{40}{x}=\dfrac{100\%}{75\%}$
$\Rightarrow \dfrac{40}{x}=\dfrac{100}{75}$
Taking the reciprocal on both sides, we get,
$\Rightarrow \dfrac{x}{40}=\dfrac{75}{100}$
Isolating the variable $x$ by cross multiplying,
$\Rightarrow x=\dfrac{\left( 75\times 40 \right)}{100}$
Simplifying the above equation, we get,
$\Rightarrow x=\dfrac{3000}{100}$
Cancelling out the common factors, we get,
$\therefore x=30$