S3 Edexcel Central Limit Theorem Exercise 3D question 11

Hey,

(Note that I understand the theory, this is just a question about why the inequality sign is that way round)

Okay so the complete question and answer is attached for reference

For part (b), shouldn't the inequality be < 1.96 rather than > 1.96?

Instead of using a mod, I just spelt it out as in between -10 and 10, and I keep getting < 1.96

Any help would be much appreciated!

If I follow the query correctly I also make it greater than 1.96

Whenever your free, is it possible you could send your working out?

tomorrow evening I might do the question for you ... I finish work at 20.00

tomorrow evening I might do the question for you ... I finish work at 20.00

Bumppp

will eat , catch up with the day, then I will do your question

Sweet!

Thank you! How do I not get the same? (See last line)


Posted from TSR Mobile

your method is incorrect ...
there is no 1 - .... in part 2

Are you referring to

P(X < 10/n) is same as 1 - P(X > 10/n)

being incorrect?

yes ... because the other side is fine as it is

yes ... because the other side is fine as it is

I tried to get it into (P > x) form so that I could use a % table value

that is where you are wrong ... it is the other way round

Have a look at some simple inversions here