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Alevel help with further maths watch

1. The random variable X takes values 2,4,6,...1000 with equal probabilities. Find from first principles the variance of X.

Anyone that can help me with this problem? It would be much appreciated!
2. I have been stuck on this problem for ages... does anyone have any idea how to even start solving it?
3. (Original post by Ioanna13)
The random variable X takes values 2,4,6,...1000 with equal probabilities. Find from first principles the variance of X.

Anyone that can help me with this problem? It would be much appreciated!

I've done this- i think this is first principle enough but if not I can try and prove parts of this solution too.
4. It is! Thank you very much! You saved my life
5. I also have another question on this paper... nice handwriting by the wat
7. I managed to proof the first part but can you give me any pointers for part b?
Attached Images

8. (Original post by ZaraHuss)

I've done this- i think this is first principle enough but if not I can try and prove parts of this solution too.
Also can you pleeeaaasee explain to me the part of Σ/n? Why did you do that?
9. (Original post by Ioanna13)
Also can you pleeeaaasee explain to me the part of Σ/n? Why did you do that?
So the expected value of x is just summation of all the x values divided by the number there are. That can be written as Σ/n. Similarly for x^2! The formulae that follow this I learnt in Edexcel FP1 (I don't know if you're doing a different exam board but it's in the formula book for Edexcel)
10. I am doing AQA. I will check our formulae booklet! Again thank you very much
11. (Original post by Ioanna13)
The quality isn't very good of this- can you just send the question, or with a better resolution and i can have a go.
14. (Original post by Ioanna13)
Is this better?
15. (Original post by Ioanna13)
It is! Thank you very much! You saved my life
16. (Original post by joyoustele)
Oh yeah hahahahhaha
17. This is Further Maths 2017?

I swear it's core 1, core 2, FP1, FP2? You don't have to do statistics.
18. (Original post by thekidwhogames)
This is Further Maths 2017?

I swear it's core 1, core 2, FP1, FP2? You don't have to do statistics.
I am doing Further Maths AQA 2018, it is the new linear course
19. (Original post by thekidwhogames)
This is Further Maths 2017?

I swear it's core 1, core 2, FP1, FP2? You don't have to do statistics.
In the new A-Level Maths you do. Statistics in FM is optional.
20. (Original post by Black Water)
In the new A-Level Maths you do. Statistics in FM is optional.
Are you sure? Because it is a very new Alevel

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