A savings scheme makes the investment double in 7 years. Find the rate of interest accrued if compounded annually. [Given log 2 = 0.30103, log (1.10409) = 0.043].

In an examination 45% of the candidates have passed in English, 40% have passed in Bengali, while 30% have passed in both the subjects. Find the total number of candidates if 90 of them have failed in both the subjects.