Maths & Physics Help

[astarmathsandphysics]

Hi my exam's in 12 hours, and I just don't get statistics. Please help with this question,

Consider the 10 data items x1, x2, ... x10. Given that Sum(x_i)  = 1341 and the standard deviation is 6.9, find the value of the mean .

The answer is:

6.9² = 1341/10 - mean²

and then the answer works out to be +/- 9.3 .

I get the method, I just don't get why they divided by 10 ?

Did you mean Sum(x_i²)?

[roma]

It doesn't work

[astarmathsandphysics]

what doesnt work?

[haziq91]

Can anyone help me with this coursework..  I can't do q1   and question 2.....   they are quite difficult...


thanks in advance

[astarmathsandphysics]

I will do it tomorrow morning.

[haziq91]

thank you very much but can u plz posted it b4 12pm as i have to hand it in at 2 pm

[astarmathsandphysics]

I noticed that.

[astarmathsandphysics]

q3 needs software

[haziq91]

thanks man...  it did help with some of the confusion that i had

[astarmathsandphysics]

No probs

[astarmathsandphysics]

I asked a coursework company how much they would charge to do it. They said £180.