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# S2 Edexcel Rectangular Uniform Distribution help! watch

1. Q: https://gyazo.com/f033abbe5197078acbb3f527c67ac7e9
A: https://gyazo.com/fdf85b44a6e85a25510cb07b4780157b
Can you please explain question D, I don't get how E(R) is related to Var(X) and E(X^2). Also can you explain the alternate method too? Thanks in advance
Q: https://gyazo.com/f033abbe5197078acbb3f527c67ac7e9
A: https://gyazo.com/fdf85b44a6e85a25510cb07b4780157b
Can you please explain question D, I don't get how E(R) is related to Var(X) and E(X^2). Also can you explain the alternate method too? Thanks in advance
Surely you should know that since then

.

So since .

Plugging this into the previous equation yields

The alternative method is just using the fact that .

You really need to include more of your own thoughts and attempts instead of just asking for an explanation. Keep that in mind next time.
3. (Original post by Zacken)
Surely you should know that since then

.

So since .

Plugging this into the previous equation yields

The alternative method is just using the fact that .

You really need to include more of your own thoughts and attempts instead of just asking for an explanation. Keep that in mind next time.
Ahhh the hero is saving the day again. Stats isn't my strongest point so forgive me for that

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