In this post, we’re going to learn “**How to find the percentage of any given quantity? “**.Suppose you visit the shopping mall in your town for new clothes, and the seller says, you will get a 30 % discount on this product. Now, how you will calculate that amount?

Q.1 Find 30 % of 260 Rs

Solution : Let 30 % of 260 Rs is x

We know ,Operator **“of “** used for multiplication

∴ 30% × 260 = x

\frac{30}{100}×260 = x [ 30 % can be written as \frac{30}{100}

x =26×3

x = 78 Rs

So, 30 % of 260 Rs is 78 Rs

Q.2 Find 75 % of 12

Solution : Let 75 % of 12 be x

∴ \frac{75}{100} of 12 = x

\frac{75}{100} × 12 = x

\frac{3}{4}×12= x

3 × 3 = x

So, 75 % of 12 is 9

Q.3 Find 45 % of 1 km

Solution:

Let 45 % of 1 km is x

∴ 45 % × 1 km = x

We know , 1 km = 1000 m

45 % ×1000 = x

\frac{45}{100} ×1000 = x

45 × 10 = x

x = 450 metre

So, 45 % of 1 km is 450 metre

Q.4 Find 8 % of the 48 litres milk

Solution :

Let 8 % of 48 litres milk is x

∴ 8 % of 48 = x

\frac{8}{100} × 48 = x

\frac{2}{25} × 48 = x

2× 48 = 25 x

96 = 25x

x = 3. 84

So, 8 % of the 48 litres milk is 3. 84 litres

Here are some word problems based on the concept of percentage of quantity

Q.1 A man spends 80 % of his salary. If he gets 12, 500 Rs per month as salary, find his monthly savings

Solution :

Monthly salary of man = 12, 500 Rs

Amount of salary, he spends per month = 80 % of 12,500 Rs

Amount of salary , he spend per month = \frac{80}{100} ×12,500 = 80 ×125 = 10,000 Rs

We know , savings + expenses = salary

Savings + 10,000 = 12,500

Saving = 12,500 – 10,000

Saving = 2,500 Rs

Q.2 A shop has 500 bulbs, out of which 75 are defective. What percentage of bulbs is defective

Solution:

Total number of bulbs in the shop = 500 bulbs

No. of defective bulbs = 75 bulbs

Percentage of defective bulbs = \frac{75}{500}×100

= \frac{75}{5}

= 15 %

Q.3 A basket contains 260 apples. If 15 % of the apples were rotten, find the number of apples good enough to be sold.

Solution :

No . of apple in the basket = 260 apples

No. of rotten apples in the basket= 15 % of 260 apples

= \frac{15}{100}× 260

= \frac{3}{2}× 26

=3× 13

= 39 apples

No . of good apples in the basket = 260 – 39 = 221 apples

Check these resources as well