16-10 Effective Cost of Trade Credit

The D. J. Masson Corporation needs to raise $500,000 for 1 year to supply working capital to a new store. Masson buys from its suppliers on terms of 3/10, net 90 and it currently pays on the 10th day and takes discounts. However, it could forgo the discounts, pay on the 90th day and thereby obtain the needed $500,000 in the form of costly trade credit. What is the effective annual interest rate of this trade credit?

The Answer is--14.91--show all work and formulas to support answers.