Assuming a face value (F) of $1000, we are given the following data:
present value or bond value, b = $1125.25
Rate of return = 6.55%
Coupon payment, C = 1000 x6.55% = $65.5
Time to maturity, t = 19 years
Number of intervals (given semi-annual interest payments) = 38
Using the equation for bond price,
bond price = (C/2) (1-[(1+YTM/2)^(-2t)])/(YTM/2) + F/[(1+(YTM/2)^t]
we can calculate the yield to maturity (YTM) as 5.48%.
You can also use a helpful link at http://www.investopedia.com/ask/answers/012015/how-do-i-calculate-yield-maturity-excel.asp to calculate the same using an easy excel function.
hope this helps.