Please show work for calculations and formulas to understand better (no excel)

Assume you purchased a Caesars Bond one year ago for $802.47 when the market rate of interest (YTM) was 10%. This bond 30 years until maturity at the time of purchase and is contracted to pay a semiannual coupons at the rate of 7.5%. If the current market rate of interest (YTM) is 8%, what would be the percentage change in bond value from the time you purchased this bond until today? hint: just compute the price today taking into consideration of the fact that the bond has one year less left to maturity now, and then calculate the percentage change in bond price from one year ago to today. For this purpose, only consider price change, no coupon is to be included