# Ex.8.2 Q4 Compairing Quantities - NCERT Maths Class 7

## Question

Find:

(a) $$15\%\, {\rm{ of }}\,250$$

(b) $$1\% \,{\rm{ of\, }}1\,{\rm{ hour }}$$

(c) $$20\% \,{\rm{ of \,Rs\, }}2500$$

(d) $$75\%\, {\rm{ of \,}}1{\rm{kg}}$$

Video Solution
Comparing Quantities
Ex 8.2 | Question 4

## Text Solution

What is Known?

Some quantities (numbers).

What is Unknown?

The per cent of the given quantities (numbers).

Reasoning:

First convert the given percentage into fraction by dividing it by $$100$$ then multiply it with the given quantity (number) to get the answer.

Steps:

(a) \begin{align}15\% {\text{ of }}250\\ 15\% &= \frac{{15}}{{100}}\\ 15\% {\text{ of }}250 \, &= \frac{{15}}{{100}} \times 250\\ &= 37.5\%\end{align}

(b) \begin{align}1\% {\text{ of }}1{\rm{ hour }}\\ 1\% &= \frac{1}{{100}}\\1\% {\rm{ of }}1{\text{ hour }} &= \frac{1}{{100}} \times 60{\text{min}}\\ &= 0.6{\rm{ minutes }}\end{align}

(c)  \begin{align}20\% {\text{ of Rs }}2500\\ 20\% \, &= \frac{{20}}{{100}}\\\,\,\,\,\,\,20\% {\text{ of Rs }}2500\, &= \frac{{20}}{{100}} \times 2500\\ &= {\text{Rs}}\,500\end{align}

(d)  \begin{align}75\% {\text{ of }}1{\text{kg}}\\75\% &= \frac{{75}}{{100}}\\75 \% {\text{ of }}1{\text{kg}} &= \frac{{75}}{{100}}{\rm{x}}1000{\text{gms}}\\& = 750{\text{gms}}\end{align}

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