What is $$25\% $$ of $$30\% $$ of $$400$$ ?

Question

What is  $$25\% $$  of  $$30\% $$  of  $$400$$ ?

Vedantu Content Team · Accepted Answer

Hint: In the question we are asked to find $$25\% $$  of  $$30\% $$  of  $$400$$ . So, we will first try to find the $$30\% $$  of  $$400$$ , and whatever we get as the result we will try to find out  $$25\% $$  of that number.Here, we will use the concept that  $$x\% $$  of any number  $$y$$  is given as; $$y \times \dfrac{x}{{100}}$$ .Complete step-by-step answer:In the question we are asked to find $$25\% $$  of  $$30\% $$  of  $$400$$ . So, we will first try to find the $$30\% $$  of  $$400$$ , and whatever we get as the result we will try to find out  $$25\% $$  of that number.Here, we will use the concept that  $$x\% $$  of any number  $$y$$  is given as; $$y \times \dfrac{x}{{100}}$$ .Step by step solution:Given question:  $$25\% $$  of  $$30\% $$  of  $$400$$ In order to solve the question, we will first find  $$30\% $$  of  $$400$$ .Now we know that; $$x\% $$  of  $$y$$  $$ = y \times \dfrac{x}{{100}}$$ So, we get; $$ \Rightarrow 30\% $$  of  $$400$$  $$ = 400 \times \dfrac{{30}}{{100}}$$ Now we will simplify the RHS. So, we get; $$ \Rightarrow 30\% $$  of  $$400$$  $$ = 4 \times 30$$  $$ \Rightarrow 30\% $$  of  $$400$$  $$ = 120$$ Now we will find  $$25\% $$  of  $$120$$ .We know that, $$x\% $$  of  $$y$$  $$ = y \times \dfrac{x}{{100}}$$ So, $$ \Rightarrow 25\% $$  of  $$120$$  $$ = 120 \times \dfrac{{25}}{{100}}$$ On further simplification we get; $$ \Rightarrow 25\% $$  of  $$120$$  $$ = \dfrac{{120}}{4}$$ So, we get; $$ \Rightarrow 25\% $$  of  $$120$$  $$ = 30$$ Hence,  $$25\% $$  of  $$30\% $$  of  $$400$$  $$ = 30$$ So, the correct answer is “30”.Note: The capability of representing any number or quantity on the basis ''of''  $$100$$  is called percentage.For example: $$x\%  = \dfrac{x}{{100}}$$ One point to note here is that, while calculating the percentage, the same units should be used. For example; if the question is like ten paisa is what percent of one rupee. So here we see that paisa and rupee are not the same units. So, we will convert either paise to rupee or rupee to paisa and then find the percentage.Another point to note is that while finding  $$25\% {{ \;''of'' \;120}}$$ , we have used the formula but we can also find it directly by dividing  $$120{{ \;by \;4}}$$ . Similarly, to find  $$20\% $$  of a number we can divide that number directly by  $$5$$  in order to get the answer.

What is \[25\% \] of \[30\% \] of \[400\] ?