Consider a 30-year corporate bond paying 9 percent semi-annual coupon. The current yield to maturity is 11 percent. Find the modified duration.

Consider a 30-year corporate bond paying 9 percent semi-annual coupon. The current yield to maturity is 11 percent. Find the modified duration. If the interest changes by 25 basis points, what us the exact change in price? If the interest changes changes by 25 basis points, what is the approximate change in price?