Let the rate of S.I. be r% per annum. ∴ Time = r years S.I. = 100Principle×Time×Rate​ C.I. = Principal [(1+100Rate​)Time−1] According to the question 100P×r×r​ = P [(1+100r​)2−1]100r2​ = 1 + 10000r2​+1002r​ - 1 ⇒ 100r​ = 10000r​+501​ ⇒ 100r​−10000r​ = 501​ ⇒ 10000100r−r​ = 501​ ⇒ 99r = 5010000​ = 200 ⇒ r = 99200​ = 2 992​ % per annum