Ram bought a cell phone and paid 30% less than its original price. He sold it at 50% profit on the price he had paid. The percentage of profit earned by Ram on the original price was:

A watch is purchased for ₹3,200 and sold for ₹2,700. Calculate the percentage loss up to two places of decimal.

The marked price of an article is 40% above its cost price. If its selling price is $73{1 \over 2}$% of the marked price, then the percentage profit is:

Sita sold a whiteboard marker set at 10% profit. On selling it for Rs. 20 more, she would have earned a profit of 15%. What is the cost price of the whiteboard marker set?