You are Here: Home >< Maths

S2 Question? Binomial distribution?

Announcements Posted on
Four hours left to win £100 of Amazon vouchers!! Don't miss out! Take our short survey to enter 24-10-2016
1. the mean= 3
the variance is 2.25

Find P( mean- variance < X is less than or equal to the mean)

How do you do this please?
2. (Original post by APersonYo)
the mean= 3
the variance is 2.25

Find P( mean- variance < X is less than or equal to the mean)

How do you do this please?
Have you substituted the terms in the inequality to get something that looks like
($P( a \leq X \leq b)$)
where a and b are numbers?
3. (Original post by SeanFM)
Have you substituted the terms in the inequality to get something that looks like
($P( a \leq X \leq b)$)
where a and b are numbers?
Yes. I got
4. (Original post by APersonYo)
Yes. I got
I see someone has edited your post so I'm not 100% sure what you originally said.. that is not your fault, I think someone is trying to help you format it correctly.

But yes, you're right, you need to find
($P( 0.75 < X \leq 3)$)

Do you know how to solve it from there? no worries if you don't. (I dropped a very subtle hint in my earlier post where I've turned it into the form )

Register

Thanks for posting! You just need to create an account in order to submit the post
1. this can't be left blank
2. this can't be left blank
3. this can't be left blank

6 characters or longer with both numbers and letters is safer

4. this can't be left empty
1. Oops, you need to agree to our Ts&Cs to register

Updated: October 13, 2016
TSR Support Team

We have a brilliant team of more than 60 Support Team members looking after discussions on The Student Room, helping to make it a fun, safe and useful place to hang out.

This forum is supported by:
Today on TSR

Who is getting a uni offer this half term?

Find out which unis are hot off the mark here

Poll
Useful resources

Maths Forum posting guidelines

Not sure where to post? Read here first

How to use LaTex

Writing equations the easy way

Study habits of A* students

Top tips from students who have already aced their exams

Chat with other maths applicants