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Ques 1 GATE 2024 SET-2
A person sold two different items at the same price. He made 10% profit in one item, and 10% loss in the other item. In selling these two items, the person made a total of
(c) is the correct answer.
Let the Selling Price (SP) of each item = ₹100
For Item 1 (10% Profit):
SP = CP × (100 + Profit%) ÷ 100
100 = CP × 110 ÷ 100
CP = 100 × 100 ÷ 110
CP1 = ₹90.91
For Item 2 (10% Loss):
SP = CP × (100 − Loss%) ÷ 100
100 = CP × 90 ÷ 100
CP = 100 × 100 ÷ 90
CP2 = ₹111.11
Total SP = 100 + 100 = ₹200
Total CP = 90.91 + 111.11 = ₹202.02
Since Total CP > Total SP, there is a Loss
Net Loss = 202.02 − 200 = ₹2.02
Loss% = (Net Loss ÷ Total CP) × 100
Loss% = (2.02 ÷ 202.02) × 100
Loss% = 1%
Shortcut Formula:
Net Loss% = (Common%)2 ÷ 100
Net Loss% = (10)2 ÷ 100
Net Loss% = 100 ÷ 100
Net Loss% = 1%
The person made a net loss of 1%
Ques 2 GATE 2021

(c) is the correct answer.
Item P: Cost = ₹5,400, Marked Price = ₹5,860, Profit% = ---
Item Q: Cost = ---, Profit% = 25, Marked Price = ₹10,000
Ratio of Cost of P to Cost of Q = 3:4
Step 1: Find Cost of Item Q
Cost of P ÷ Cost of Q = 3 ÷ 4
5,400 ÷ Cost of Q = 3 ÷ 4
Cost of Q = 5,400 × 4 ÷ 3
Cost of Q = ₹7,200
Step 2: Find Selling Price of Item Q
Profit% = (SP − Cost) ÷ Cost × 100
25 = (SP − 7,200) ÷ 7,200 × 100
SP − 7,200 = 25 × 7,200 ÷ 100
SP − 7,200 = 1,800
SP = 7,200 + 1,800
SP of Q = ₹9,000
Step 3: Find Discount on Item Q
Discount = Marked Price − Selling Price
Discount = 10,000 − 9,000
Discount = ₹1,000
Step 4: Find Discount as % of Marked Price
Discount% = (Discount ÷ Marked Price) × 100
Discount% = (1,000 ÷ 10,000) × 100
Discount% = 10%
The discount on item Q as a percentage of its marked price = 10% (Option C)
Ques 3 GATE 2020
The revenue and expenditure of four different companies P, Q, R and S in 2015 are shown in the figure. If the revenue of company Q in 2015 was 20% more than that in 2014, and company Q had earned a profit of 10% on expenditure in 2014, then its expenditure (in million rupees) in 2014 was ________.

(c) is the correct answer.
From the graph, Revenue of Q in 2015 = ₹45 million
Revenue in 2015 = Revenue in 2014 × 1.20
45 = Revenue in 2014 × 1.20
Revenue of Q in 2014 = 45 ÷ 1.20 = ₹37.5 million
Let expenditure in 2014 = x million rupees
Profit% = (Revenue − Expenditure) ÷ Expenditure × 100
10 = (37.5 − x) ÷ x × 100
10x = 3750 − 100x
110x = 3750
x = 3750 ÷ 110
x = 34.09 ≈ 34.1 million rupees
The expenditure of company Q in 2014 = 34.1 million rupees (Option C)
Ques 4 Gate 2014 Set-1
Round-trip tickets to a tourist destination are eligible for a discount of 10% on the total fare. In addition, groups of 4 or more get a discount of 5% on the total fare. If the one way single person fare is Rs 100, a group of 5 tourists purchasing round-trip tickets will be charged Rs _________.
(₹855) is the correct answer.
One way single person fare = ₹100
Round-trip fare for 1 person = 100 × 2 = ₹200
Total fare for 5 persons = 200 × 5 = ₹1000
Discount 1 (Round-trip discount) = 10% of 1000 = ₹100
Fare after first discount = 1000 − 100 = ₹900
Discount 2 (Group of 5 discount) = 5% of 900 = ₹45
Fare after second discount = 900 − 45 = ₹855
A group of 5 tourists purchasing round-trip tickets will be charged ₹855
Ques 5 GATE 2013
A firm is selling its product at Rs. 60 per unit. The total cost of production is Rs. 100 and firm is earning total profit of Rs. 500. Later, the total cost increased by 30%. By what percentage the price should be increased to maintained the same profit level?
(a) is the correct answer.
Selling Price per unit = ₹60
Total Cost = ₹100
Total Profit = ₹500
Total Revenue = Total Cost + Total Profit
Total Revenue = 100 + 500 = ₹600
Number of units = Total Revenue ÷ Price per unit
Number of units = 600 ÷ 60 = 10 units
New Total Cost after 30% increase = 100 × 1.30 = ₹130
To maintain same profit of ₹500:
New Total Revenue = New Total Cost + Profit
New Total Revenue = 130 + 500 = ₹630
New Price per unit = 630 ÷ 10 = ₹63
Increase in price = 63 − 60 = ₹3
Price increase% = (3 ÷ 60) × 100 = 5%
The price should be increased by 5% (Option A)