SOLUTION: Several layers of plastic are stacked together.Each layer reduces the light passing through it by 5%(percent).How many layers of plastic are needed to reduce the intensity to only

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Question 376080: Several layers of plastic are stacked together.Each layer reduces the light passing through it by 5%(percent).How many layers of plastic are needed to reduce the intensity to only 1% of the original light.
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
I=I%5B0%5D%2A%280.95%29%5En
0.01=0.95%5En
n=log%280.95%2C%280.01%29%29
n=log%28%280.01%29%29%2Flog%28%280.95%29%29
highlight%28n=%28-2%29%2Flog%28%280.95%29%29%29
or approximately,
n=89.78
Round up to n=90