Solution -
CP of car = 3,00,000
SP of car = 3,00,000 + 3,00,000 (10/100)
= 3,00,000 + 30,000
= 3,30,000
CP of bike = 1,00,000
SP of bike = 1,00,000 - 1,00,000 (20/100)
= 1,00,000 - 20,000
= 80,000
Total CP of car and bike = 3,00,000 + 1,00,000
= 4,00,000
Total SP of car and bike = 3,30,000 + 80,000
= 4,10,000
Net profit = [{(SP - CP)/CP} × 100]
= [{(4,10,000 - 4,00,000) / 4,00,000} × 100]
= 10,000 / 4,000
= 5/2
= 2.5%
Therefore
The net profit is 2.5%.
Hence,
The correct answer is option (d) 2.5% gain.
Thank You