A boy bought a camel and carriage for Tk 5000. He sells the camel at a gain of 20% and the carriage at a loss of 10%. If he gains 3% on the whole, then find the cost of the camel.

Now, in this numerical, there is no common loss and gain %.
Hence, solve it by making equations.

Let the cost price of the camel be x.
As the cost of camel and carriage = Tk 5000
Cost of carriage = Tk (5000 – x)
After selling the camel he gains 20% and on carriage a loss of 10%. But on the whole, he gains 3%.

Therefore,
20% of x – 10% of (5000 – x) = 3% of 5000
⇒ (20/100) × x - (10/100) × (5000 – x) = (3/100) × 5000
⇒ x/5 - (5000 – x)/10 = 150
⇒ 10x/5 - {(5000 – x) × 10}/10 = 150 × 10
⇒ 10x/5 - (5000 – x) = 1500
⇒ 2x - 5000 + x = 1500
⇒ 3x=1500 + 5000
⇒ x = 2166.67.
The cost of camel = Tk. 2166.67