What is the equivalent fraction to 13/15

Determine the mean and variance of the random variable with the following probability mass function. f(x)=( 729divided by 91) (1 divided by 9) superscript x baseline comma x equals 1,2,3 round your answers to three decimal places (e.g. 98.765).

On a piece of paper graph f(x)=5•(0.4)^x

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