How much quantity (in kg) of wheat costing Rs 84 per kg must be mixed with 81 kg of wheat costing Rs 60 per kg so that on selling the mixture at Rs 75.9 per kg, there is a gain of 15%?
A shopkeeper purchased 10 boxes of pencils containing 10 pencils each at Rs. 100 per box and sold each pencil at a profit 12%. What is the total sale price?
The marked price of a calculator is Rs 750. It is sold at a discount of 22%. If the cost price of the calculator is Rs 500, then what is the profit (in Rs)?