If simple interest earned on a certain sum for the 4 years is Rs. 19,200 and compound interest earned in 2 years is Rs. 10,200/-, then find the rate of interest p.a.
Answer & explanation
Correct answer: option 3
S.I. is constant for each year
⇒ S.I. in 4 year = Rs.19200/-
⇒ S.I. in 1 year =\(\frac{19200}{4}\) = Rs. 4800/-
⇒ S.I. in 2 year =\(\frac{19200}{2}\) = 9600
⇒ C.I. in 2 years = Rs.10200/-
Difference b/w C.I. and S.I. = 10200 - 9600 = 600
⇒ Rate of Interest = \(\frac{(600) × 100}{4800}\)
⇒ R = 12.5%