How to find E(1/X)?

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Can someone please explain to me how to do question 7d? Thanks heaps!

1 Answer
Jan 13, 2018

0.12(2dp)

Explanation:

#for discrete pdf

E(f(x))=all xf(x)P(X=x)

so

E(1x)=all x(1x)P(X=x)

putting this into a table for ease of calculation

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E(1X)=0.005+0.838383..+0.01+0.006+0.0066

E(1X)=0.1150..=0.12(2dp)