can someone explain how we get (i=0.015, n=30) =24.016

Explain step by step the question please. Thank you.

On December 31, 2017, $310,000 of 4% bonds were issued. The market interest rate at the time of issuance was 3%. The bonds pay interest on June 30 and December 31 and mature in 15 years. Required: Compute the selling price of a single $1,000 bond on December 31, 2017. Note: Round all intermediate calculations to three decimal places, and round your final answer to the nearest cent. 0 Selling price of bonds: x 5