Hello. I need help on how to find the yield to maturities and the duration of the bonds using a formula. The solution tells me to use excel but I would like to know how to get the answers manually. Thanks in advance.

Assume coupons are paid annually. Here are the prices of three bonds with 10-year maturities Bond Coupon(%) Price (96) 81.62 98.39 133.42 4 a. What is the yield to maturity of each bond? (Do not round intermediate calculations. Enter your answers as a percent rounded to 2 decimal places.) Bond Coupon (96) YTM 4.30 % 4.200 % 3.90 0 % 4 b. What is the duration of each bond? (Do not round intermediate calculations. Round your answers to 2 decimal places.) Bond Coupon (96) Duration 9.05 years 8.42 years 7.65 years 4