CAT (QA) PYQs

A person spent Rs $50000$ to purchase a desktop computer and a laptop computer. He sold the desktop at $20$ profit and the laptop at $10$ loss. If overall he made a $2$ profit then the purchase price, in rupees, of the desktop is

A wholesaler bought walnuts and peanuts, the price of walnut per kg being thrice that of peanut per kg . He then sold $8 \mathrm{~kg}$ of peanuts at a profit of $10 \%$ and $16 \mathrm{~kg}$ of walnuts at a profit of $20 \%$ to a shopkeeper. However, the shopkeeper lost $5 \mathrm{~kg}$ of walnuts and $3 \mathrm{~kg}$ of peanuts in transit. He then mixed the remaining nuts and sold the mixture at Rs. $166$ per kg, thus making an overall profit of $25 \%$. At what price, in Rs. per kg, did the wholesaler buy the walnuts?

One part of a hostel's monthly expenses is fixed, and the other part is proportional to the number of its boarders. The hostel collects $1600$ per month from each boarder. When the number of boarders is $50$, the profit of the hostel is $200$ per boarder, and when the number of boarders is $75$, the profit of the hostel is $250$ per boarder. When the number of boarders is $80$, the total profit of the hostel, in INR, will be