CAT (QA) PYQs

On selling a pen at $5 \%$ loss and a book at $15 \%$ gain, Karim gains Rs. $7$. If he sells the pen at $5 \%$ gain and the book at $10 \%$ gain, he gains Rs. 13. What is the cost price of the book in Rupees?

Mayank buys some candies for Rs $15$ a dozen and an equal number of different candies for Rs $12$ a dozen. He sells all for Rs $16.50$ a dozen and makes a profit of Rs $150$. How many dozens of candies did he buy altogether?

Bina incurs 19% loss when she sells a product at Rs. 4860 to Shyam, who in turn sells this product to Hari. If Bina would have sold this product to Shyam at the purchase price of Hari, she would have obtained 17% profit. Then, the profit, in rupees, made by Shyam is