Bond Pricing change, someone, interest, structure, percentage

clearlycanadian

Can someone explain this:

Consider a bond that pays an annual coupon of 5% and that has three years remaining until maturity. Assume the term structure of interest rates is flat at 6%. If the term structure of interest rates does not change over the next twelve-month interval, the bond's price change (as a percentage of par) will be closest to:

Answer:

The bond price change is computed as follows:

Bond Price Change = New Price − Old Price = (5/1.06 + 105/1.062) − (5/1.06 + 5/1.062 + 105/1.063) = 98.17 − 97.33 = 0.84.

I don't understand the logic behind the new price and the old price.