India hold its first-ever lobal tourism mart at Vigyan Bhawan, New Delhi from september 16-18. It is modelled on the ITB Berlin, the world's largest tourism trade fair.
Cost price of a pen is 50 Rs. and that of notebook is 140 Rs. If pen is sold at 200% profit, then to purchase 10 such note books how many pens are required to sell if only profit money is used to buy notebooks?