Question

Evaluate \[30\% \] of \[70\% \] of \[\dfrac{3}{5}\]th of 3500.

a.441
b.361
c.400
d.484

Answer 1

Hint: We have to find the value of \[30\% \] of \[70\% \] of \[\dfrac{3}{5}\]th of 3500. For this, we find \[\dfrac{3}{5}\]th of 3500 first.
Now note that \[x\% \] of a number n is given by $n \times \dfrac{x}{{100}}$. Therefore find 30% of 70% of \[\dfrac{3}{5}\]th of 3500.

Complete step-by-step answer:
We have to find the value of 30% of 70% of \[\dfrac{3}{5}\]th of 3500.
Now, \[\dfrac{3}{5}\]th of 3500 is given by
$ = 3500 \times \dfrac{3}{5}$
On simplification we get,
$ = 700 \times 3$
On multiplication we get,
$ = 2100$
Now, \[70\% \] of \[\dfrac{3}{5}\]th of 3500
\[ = 70\% \] of 2100
Using, \[x\% \] of a number n is given by $n \times \dfrac{x}{{100}}$, we get
$ = 2100 \times \dfrac{{70}}{{100}}$
On simplification we get,
$ = 21 \times 70$
On multiplication we get,
$ = 1470$
Now, \[30\% \] of \[70\% \] of \[\dfrac{3}{5}\]th of 3500 is
\[ = 30\% \] of 1470
Using, \[x\% \] of a number n is given by $n \times \dfrac{x}{{100}}$, we get
\[ = 1470 \times \dfrac{{30}}{{100}}\]
On cancelling zeros we get,
$ = 147{0} \times \dfrac{{3{0}}}{{1{0}{0}}}$
$ = 147 \times 3$
On multiplication we get,
$ = 441$
Therefore \[30\% \] of \[70\% \] of \[\dfrac{3}{5}\]th of 3500 is 441.

Hence the correct option is (A).

Note: In mathematics, a percentage is a number or ratio that represents a fraction of 100. It is often denoted by the symbol " \[\% \]" or simply as "percent" or "pct." For example, 35\[\% \] is equivalent to the decimal \[0.35\], or the fraction \[\dfrac{{35}}{{100}}\].