1544000/((1+r)^8)=504736 cross multiply
504736(1+r)^8 = 1544000 divide both sides by 504736
(1+r)^8 = 3.0590249 take the 8th root of both sides
1+r = 3.0590249^(1/8)
1+r = 1.15 subtract 1 from both sides
r = 1.15 - 1
r = 0.15 x 100 multiply by 100
r = 15%
