The rate of simple interest on a sum of money is 5% p.a. for the first 4 years, 8% p.a. for the next 3 years and 10% p.a. for the period beyond 7 years. If the simple interest accrued by the sum over a period of 10 years is Rs.1,850, then the sum is :

Mr. A bought a laptop with \(16 {{2} \over 3}\) % discount on the labeled price. Had he bought it with 25% discount, he would have saved Rs 600. At what price did he buy the laptop?

A, B and C can individually complete a task in 24 days, 20 days and 18 days, respectively. B and C start the task, and they work for 6 days and leave. The number of days required by A alone to finish the remaining task is: