Digital Sum part 2

The digital root of a number is obtained by adding together the digits of that number, and repeating that process until a number is arrived at that is less than 1010.

For example,for 2995329953 the digital root is 299532810129953 \rightarrow 28\rightarrow 10\rightarrow 1.

Consider the set PP of all prime numbers less than two million.If xx is the percentage of numbers in PP with a digital root of 2,what is the value of 1000x\left\lfloor 1000x \right\rfloor ?

Details and assumptions

x\left\lfloor x \right\rfloor is the floor function and it returns the greatest integer less or equal to xx. ie 1.234=1\left\lfloor 1.234 \right\rfloor =1


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