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The numbers from 1 to 150, inclusive, are placed in a bag and a number is randomly selected from the bag. What is the probability it is not a perfect power (integers that can be expressed as $x^y$ where $x$ is an integer and $y$ is an integer greater than 1. For example,$2^4=16$  is a perfect power, while $2*3=6$ is not a perfect power)? Express your answer as a common fraction.