If it "loses .25% of its volume", it retains 1- 0.0025= .9975 or 99.75% of its volume. Let V be the initial volume. Then the second day its volume is .9975V. The third day it is .9975 times that: . The fourth day it is .9975 timesthat: .

Get the point? This is a "geometric series". After n days, its volume will be .

i) What is ?

ii) Solve [/tex].9975^{n-1}= .75 (You may need to use logarithms.)