Hiralal gave a loan of Rs. 20 to Ramlal and recovered it at the rate of Rs 3.50 for eight months, commencing from the end of 1st month. What is the effective rate of simple interest?
Choose one:  A) 60%  B) 80%  C) 20%  D) 90%  E) none
Explanation:   Principal = Rs 20   Amount = Rs 3.50 x 8 = Rs 28   Interest = Rs 28 - Rs 20 = Rs 8   Time = 8 months = 8/12 years   8 = 20×8×r/12×100   r = 12×100/20 = 60% p.a.   60%nswer 60%
<result>A</result>
Hiralal gave a loan of Rs. 20 to Ramlal and recovered it at the rate of Rs 3.50 for eight months, commencing from the end of 1st month. What is the effective rate of simple interest?