Question 972858
V=C(1-r)^t (raise it to the t power)

12,000=25,000(1-r)^4.5 


12000=25000(1-r)^4.5
(12000/25000) = (1-r)^4.5
0.48=(1-r)^4.5

logs of both sides
log 0.48= -0.319=4.5 log (1-r)
(-0.319/4.5)=
 -.0701=log(1-r)

Now raise each to the 10 power

0.8495=1-r
r= 0.1505 or 15.05%

(1-r)^4.5=0.48, and that is the ratio between the present and original value.