(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

The probability density function of a random variable y is:

f(y) = 100ye[itex]^{-10y}[/itex], if y>0

f(y) = 0 otherwise

What is the probability that 45y <= 10?

2. Relevant equations

E(y) = ∫yf(y)dy

Var(y) = ∫(y-E(y))f(y)dy

3. The attempt at a solution

I solved for the expected value of y and got E(y) = 0.2

I then got Var(y) = 0.02

I don't think this is a normal distribution because the PDF is not a normal

PDF. I don't know how to solve for the probability of 45y <= 10

Any help will be greatly appreciated!

1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

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# Homework Help: How to solve for probability given density function

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