Hi. Im stuck on trying to find the interest rate. I've seen others use excel or interpolation but is there a way to find it without using excel. I want to see how its done not the quick way of getting the answer.

Alwi Florida 7-32 AL Mike buys a corporate bond with a face value of $1000 for $800. The bond matures in 10 years and pays a coupon interest rate of 5%. Interest is paid every quarter. (a) Determine the effective rate of return if Mike holds the bond to maturity. (b) What effective interest rate will Mike get if he keeps the bond for only 5 years and sells it for $900