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# Chebyshevs inequality question! watch

1. jokes
2. If you've covered it, I would use the 1 sided version of Chebyshev's inequality
3. (Original post by DFranklin)
If you've covered it, I would use the 1 sided version of Chebyshev's inequality
Our teacher gave us a very very brief intro into the inequality, purpose for upper bounds closely related to the mean etc

All I know is I have to find E(x) and var(x), and as well, I dont think this question invloves sample mean as inital question says T as opposed to Sample T

Im struggling, as it was a 5 min job in the last lecture!
4. So, have you covered the 1-sided version of the inequality?
5. (Original post by DFranklin)
So, have you covered the 1-sided version of the inequality?
nope, she gave us an example involving multiple choice but it was using possion distibution as well, like eg probability you pass an exam with 10 questions given 40% is pass rate, and another with 100 questions invloving chebyshevs equations, that is all

6. Well, in that case I can't really see a better option than observing that P(T >=110) <= P(|T-80|>=30), and you can give an upper bound for this 2nd probability using the normal two-sided Cheybyshev inequality.
7. (Original post by DFranklin)
Well, in that case I can't really see a better option than observing that P(T >=110) <= P(|T-80|>=30), and you can give an upper bound for this 2nd probability using the normal two-sided Cheybyshev inequality.
ok, btw y -80 as opposed to -20,30 etc, im very wary on this topic
8. The inequality is in your signature - it shouldn't be hard to work it out which term in the inequality corresponds to which term in P(|T-80|>=30).
9. yes i see that its (30)^2 at the bottom! but why 30 im asking?
10. (Original post by DFranklin)
The inequality is in your signature - it shouldn't be hard to work it out which term in the inequality corresponds to which term in P(|T-80|>=30).

yes i see that its (30)^2 at the bottom! but why 30 im asking?
11. (Original post by the greatest)
yes i see that its (30)^2 at the bottom!
Nope. Did you forget about ?

What is the random variable you're working with here? (Answer: T).

So we have

So, what's ? What's ? etc. etc.
12. mew being the E(X) and sigma being standrad deviation?
13. (Original post by DFranklin)
Nope. Did you forget about ?

What is the random variable you're working with here? (Answer: T).

So we have

So, what's ? What's ? etc. etc.

mew being E(T) and sigma being SD??
14. I have to ask why you've put an equation in your sig if you don't understand it?

Edit: (to be clear, what you've said above is not wrong, but you shouldn't need to ask me whether it's right if you've done anything at all about Chebyshev's inequality).
15. jokes
16. jokes
17. (Original post by DFranklin)
I have to ask why you've put an equation in your sig if you don't understand it?
"Geek chic".

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