SOLUTION: The intensity of a light source varies inversely as the square of the distance from the source. If the distance from a source increases by 25%, by what percent does the intensity d

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Question 319261: The intensity of a light source varies inversely as the square of the distance from the source. If the distance from a source increases by 25%, by what percent does the intensity decrease?
Answer by devjyotsingh24(4) About Me  (Show Source):
You can put this solution on YOUR website!
Let the orginal intensity be 100 units.
Now according to the problem if distance increases by 25% i.e. 1/4 times the intensity should decrease by sqrt(1/4) times=1/2 times.
Thus decrease in intensity=1/2(100)=50 units.
Therefore % decrease=(decrease in intensity/orignal intensity)*100=50%