'V' invested Rs. 15,000 in Provident Fund 'P,' which provides 20% compound interest for two years, compounded annually. He subsequently invested the amount received from Provident Fund 'P' in another Provident Fund 'Q,' offering a% simple interest for three years. Determine the value of 'a' if the amount received by 'V' from Provident Fund  'Q' is Rs. 29,376.