Use Excel or similar for this exercise.

Consider a 30 year bond paying 3 percent coupons semi-annually and a yield-to-maturity equal to 5 percent. Find the price and duration.

Try a few different coupon rates and see how the price and duration change. Make a graph with duration on the y-axis and coupon rate on the x-axis.

Now vary the ytm instead and graph duration against ytm. Also graph duration against par, and duration against T.