A sum of money amounts to Rs. 16800 in one year and to Rs. 18144 in one and half year on the basis of interest being compounded semi -annually. Find rate percent per annum.

16%

Interest in six months = 18144 - 16800 = 1344

⇒ Rate of interest (R) = \(\frac{1344}{16800}\) × 100% = 8 % (semi annually)

Rate percent per annum = 8 × 2 = 16%