A lent Rs. 4000 to B for 2 years and Rs. 2000 to C for 4 years on simple interest at the same rate of interest and received Rs. 2200 in all from both of them as interest. The rate of interest per annum is : Choose the correct choice from the following options: A) 14 % B) 15 % C) 12 % D) 13.75 % E) 14.56 %

Rationale: explanation : let the rate of interest per annum be r % simple interest for rs . 4000 for 2 years at r % + simple interest for rs . 2000 for 4 years at r % = 2200 ( 4000 × r × 2 ) / 100 + ( 2000 × r × 4 ) / 100 = 2200 80 r + 80 r = 2200 160 r = 2200 16 r = 220 4 r = 55 r = 55 / 4 = 13.75 % answer : option d
Answer: D