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To accumulate 50,000 at the end of 3 years, deposits of 670 are made at the end of each of the first n years and 1,000 at the end of each of the next 2n years. The annual effective rate of interest is i. You are given (1+i)n=1.9 Calculate i. 6.29% 6.85\% 7.80% 8.1696 9.57%