Guddi invested some money in a bank at rate of 6% per annum. At simple interest, after 9 years, she got Rs. 8470. How much did she invest?

Rs. 5250 Rs. 6550 Rs. 6400 Rs. 5500

Rs. 5500

ROI = 6%, Time = 9 years, Simple interest for 9 years = 54%,  Amount after 9 years i.e. = 8470  So, 8470 = Principal × 154% ( 100% = Principle and 54% - Simple interest) So, Principal = \(\frac{8470 }{ 154}\) x 100 = 5500