This document provides a lecture on profit and loss calculations. It defines key terms like cost price and selling price. It provides examples of how to calculate profit when selling price is greater than cost price and loss when cost price is greater than selling price. The document also explains how to calculate profit and loss as a percentage. Several word problems are worked through as examples, including calculating profit/loss percentages and determining the selling price needed to achieve a given profit percentage. VAT (value-added tax) is also defined and an example of calculating VAT on a purchase is shown.

1. RAJUK UTTARA MODEL COLLEGE
Sector -06, Uttara Model Town, Dhaka-1230
Lecture on Profit-Loss
Lecturer :
Md. Nasim Reza
Lecturer in Mathematics (EMMS)
Rajuk Uttara Model College, Dhaka

2. Objective
 The student will understand profit and loss,
components of a simple profit and loss statement,
and the importance of profit and loss in their real
life.
 The student will also be able to calculate profit and
loss using cost price and selling price associated with
the problems..

3. The purchasing price of anything is called cost price
and the selling price of that thing is called selling
price.
For example if the cost price of a pen is Tk. 5 and
selling price is Tk. 6; then this situation is
profitable
And the profit = Selling price – Cost price.
In the above example, profit = Selling price – Cost
price.
= Tk.6 – Tk. 5
= Tk. 1

4. Again if the cost price is more than the selling price
then there is a loss.
And the loss = Cost price - Selling price.
In the above example if the cost price of a pen is Tk. 6
and selling price is Tk. 5; then
Loss = Cost price - Selling price.
= Tk.6 – Tk. 5
= Tk. 1

5. Usually Selling price and cost price are denoted by SP and CP
respectively.
Rabi bought 50 kg rice at the rate of Tk. 40 per kg and sold it at the
rate of Tk. 44 per kg. What is the amount of profit or loss?
Solution:
Here, cost of rice per kg is Tk. 40 and total amount bought is 50
kg.
So, CP = Tk. (50 x 40) = Tk. 2000
And, SP = Tk. (50 x 44) =Tk. 2200
Here, SP > CP
So profit = SP – CP
= Tk. (2200 – 2000)
=Tk. 200 (Ans.)

6. As we know by now what a selling price and cost price
is and how profit or loss can be determined by using
selling price and cost price, we will now express profit
or loss in percentage.
. Let us recall our first example
The cost price of a pen is Tk. 5 and selling price is Tk. 6;
then what is the percentage profit or loss in this case?
Here, profit = SP – CP.
= Tk.6 – Tk. 5
= Tk. 1
For Tk. 5 there is a profit of Tk. 1
For Tk. 1 there is a profit of Tk. (1 ÷5)
For Tk. 100 there is a profit of Tk. (1 ÷5) x 100= Tk.20
That is the profit is 20 % (Ans.)

7. As you can see the profit depends on the cost price. So
we can build up a formula for finding profit or loss in
percentage.
In the above problem,
Profit or Gain is Tk. 1 and Cost price is Tk. 5.
So there is a profit of 20 % (Ans.)

8. An item is bought at Tk. 190 and is sold at Tk. 175. What is the
percentage of profit or loss?
Solution:
Here, Selling price (SP) = Tk. 175
Cost price (CP) = Tk. 190
So, Cost price > Selling price. Hence there is a loss.
Loss = CP – SP = Tk. 190 –Tk. 175 = Tk. 15.

10. Rahim sold a mobile phone at the cost of Tk. 1950 at a loss
of 25 %. At what cost will he have to sell it to get a profit of 30
%?
Solution:
Here, SP = Tk. 1950, Loss = 25 %
Since the loss is 25 % we may say when the CP is Tk. 100 then
the SP is Tk. 75

11. Since the profit is 30 % we may say when the CP is
Tk. 100 then the SP is Tk. 130.
Hence Rahim will have to sell it to Tk. 3380 to get
30% profit.(Ans.)

12. Tax given at a fixed rate with the cost price of a thing is called VAT
(Value Added Tax).
Goint to a saree shop Kona bought a silk saree at Tk. 1200 and a three
piece at Tk. 1800. If the rate of VAT is Tk. 4 percent, how many taka
will she pay to the shopkeeper?
Solution:
The total price of the silk saree and three piece = 1200+1800
=Tk. 3000

13. Home Work
If the selling price of a watch is Tk. 625, the loss is 10 %.
What would be the price of the watch if a profit of 10 %
is to be gained by selling it?
If 15 ball pens are bought at Tk. 90 and are sold at Tk.
75, what is the percentage of profit or loss?