A man sold two cycles for Rs1500 each, gaining Rs20 on one and saving Rs20 on the other. Find the gain or loss percentage on the whole transaction?
$
  (a){\text{ 1}}{\text{.05% }} \\
  (b){\text{ 1}}{\text{.35% }} \\
  (c){\text{ 2}}{\text{.15% }} \\
  (d){\text{ 2}}{\text{.70% }} \\
 $

Hint: Find the cost price for both the cycles individually, using the concept that cost price is the difference of selling price and the money gained for the product. Then calculate the overall profit or loss percentage accordingly.

Complete Step-by-Step solution:
Let the cost price of the first cycle be Rs. X.
And the cost price of the second cycle will be Rs. Y.
Now it is given that the selling price of both the cycles is Rs. 1500.
Now a man gains Rs. 20 on the first cycle.
So the cost price (C.P₁) of the first cycle = selling price of the first cycle – rupees gained on the first cycle.
$ \Rightarrow C.{P_1} = 1500 - 20 = 1480$ Rs.
Now again a man saved Rs. 20 on the second cycle.
So the cost price (C.P₂) of the second cycle = selling price of the second cycle – rupees saved on the second cycle.
$ \Rightarrow C.{P_2} = 1500 - 20 = 1480$ Rs.
So the total cost price of two cycles is = (1480 + 1480) = Rs. 2960.
And the total profit he earned is = Rs. (20 + 20) = Rs. 40
Therefore a man earns the profit and the profit percentage (P) is the ratio of total profit to the total cost price multiplied by 100.
$ \Rightarrow P = \dfrac{{40}}{{2960}} \times 100 = 1.35$ %
So this is the required profit percentage.
Hence option (B) is correct.

Note: Whenever we face such types of problems involving profit or loss, the basic of cost price that is the price In which the product was purchased by the vendor, selling price that is the price at which the product was told to the customer and the relation between them helps get on right track to get the answer.