A bond portfolio consists of the following three fixed-rate bonds. Assume annual coupon payments and no accrued interest on the bonds. Prices are per $100 of par value. What is the portfolios duration?

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Market Value 270,000 230,000 300,000 Yield-to Maturity Modified Duration Maturity 6 years 10 years 15 years Price 85.0000 80.0000 100.0000 Bond Coupon 2.00% 2.40% 5.00% 4.95% 4.99% 5.00% 5.42 8.44 10.38