This document provides examples of calculating percentages. It demonstrates how to calculate percentages of amounts, find original amounts when given percentages, and calculate percentage increases or decreases. The examples show finding 40% of Rs. 150, determining the total amount when given a percentage is 40%, calculating what percentage 60 is of 150, solving for the original price of a mobile when there was a 10% discount, and determining original income when given a percentage of income paid in taxes. The final example shows calculating the percentage increase when an amount grew from Rs. 150,000 to Rs. 350,000.

1. NADEEM UDDIN
ASSOCIATE PROFESSOR
OF STATISTICS
https://www.slideshare.net/NadeemUddin17
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2. Percentage
A percentage is a ratio or fraction whose denominator is 100.
Example-1
What is 40% of Rs.150.
Solution:
40
40% of 150 = 150 Rs.60
100
 

3. Example-2
Find the sum of money of which Rs.60 is 40%.
Solution:
40% of x = 60
40
x 60
100
100
x 60 Rs.150
40
 
  

4. Example-3
What percentage of Rs.150 is Rs.60
Solution:
x of 150 = 60
x
150 60
100
100
x 60
150

 
 
x = 40%

5. Example-4
A purchaser received a discount of 10% on the selling price
of a mobile. If he paid Rs.4500, what was the selling price
of the mobile?
Solution:
Let x be the selling price
Paid percentage is 90%
Paid amount is 4500
90% 𝑜𝑓 𝑥 = 4500
90
100
. 𝑥 = 4500
𝑥 = 4500 ×
100
90
𝑥 = 𝑅𝑠. 5000

6. Example-5
What was the Abu-Tarique’s income last year if he paid
an income tax of Rs.30,000 which is 5% of his income?
Solution:
Let x be the income
5% of x = 30000
30000
100
5
 x
5
100
30000 x
x = Rs.60000 per year.

7. Example-6
The assets of a person increased from Rs.150,000 to
Rs.350,000. What was the rate of change?
Solution:
Original Amount = Rs.150,000
New Amount = Rs.350,000
Amount of Change = 350000 – 150000 = 200000
100
AmountOriginal
ChangeofAmount
ChangeofRate 
Rate of Change =
200000
150000
× 100
Rate of Change = 133.33%