A sum of money, on compound interest, amounts to ₹578.40 in 2 years and to ₹614.55 in 3 years. The rate of interest per annum, in case of annual compounding, is:
Anju ranked 18th from the bottom and 15th from the top in his class. How many students are there in his class?
The distance between the pole and focus of a spherical mirror, in terms of its radius of curvature R, is equal to: