The compound interest on a certain sum of money for 3 years, compounded annually, at a rate of interest of 10% per annum is Rs. 1,324. The sum is:

Two pipes A and B individually can fill a tank in 15 hours, and 12 hours respectively, and C can empty the full tank in 4 hour. If all three pipes are open at 8, 9, and 11 am respectively. At what time tank will be completely empty?

If 4 men and 6 boys can do a work in 8 days and 6 men and 4 boys can do the same work in 7 days, then how many days will 5 men and 4 boys take to do the same work?

The equation \(cos^2 θ= {(x+y)^2\over 4xy}\)  is only possible when