Question

Find:
(1) 20% of Rs. 2500
(2) 22% of 16000

Answer 1

Hint: Here we may use the definition of percentage to find the values given in the question. So, we know that percent mean per hundred, that is it is a number or ratio expressed as a fraction of 100.

Complete step-by-step answer:
In order to convert a number into percentage we may simply divide the number by 100 if the total is already out of 100.

For example, 20 is 20% of 100.

But for the case when the total is not 100, we may apply different methods.

So, in that case we may use proportion. A proportion basically allows us to change the problem so that the total is out of 100. Since, the percentage is also basically just a fraction, that is how many you have out of 100.

According to this proportion concept we have:

${\displaystyle \frac{part}{whole}}={\displaystyle \frac{percentage}{100}}.........(1)$

Now we may use this equation (1) to find the answers.

For case (1) we have:

The percentage is 20% and the whole is given Rs.2500.

Putting these values in equation (1) we have:

${\displaystyle \frac{part}{2500}}={\displaystyle \frac{20}{100}}$

$part={\displaystyle \frac{20}{100}}\times 2500=500$

Hence, 20% of Rs.2500 is = Rs.500.

Now for case (2) we have:

The percentage is 22% and the whole is 16,000.

Putting these values in equation (1) we have:

${\displaystyle \frac{part}{16000}}={\displaystyle \frac{22}{100}}$

$part={\displaystyle \frac{22}{100}}\times 16,000=3,520$

Hence, 22% of 16,000 is 3,520.

Note: Students should note that percentage means per hundred that is part out of 100 and that is why we are always having 100 in the denominator on the right side of equation (1).