At what rate of compound interest per annum will a sum of $1200 becomes 1348.32 in 2 years? Select
A) 5 %
B) 6 %
C) 7 %
D) 8 %
E) 10 %

Rationale: "let the rate be r % p . a . 1200 * ( 1 + r / 100 ) ^ 2 = 1348.32 ( 1 + r / 100 ) ^ 2 = 134832 / 120000 = 11236 / 10000 ( 1 + r / 100 ) ^ 2 = ( 106 / 100 ) ^ 2 1 + r / 100 = 106 / 100 r = 6 % answer is b"
Answer: B