Math Is Fun Forum
You are not logged in.
- Topics: Active | Unanswered
Pages: 1
#1 Re: Help Me ! » Standard Deviation problem » 2011-10-26 22:36:47
Thanks so much for your help took me a while to understand and was so relieved once it all clicked into place thanks again 
#2 Re: Help Me ! » Standard Deviation problem » 2011-10-21 01:41:50
Hi bobbym, thanks for taking time to have a look at this problem for me however I am still a bit confused for the second sum you done
has a total of 2.5 however I am reading it as 1.5 also for b) I look up on the table for say 2.5 which on mine relates to 0.9938 then I subtract 0.025 from it? and how do I find the new range from that?#3 Help Me ! » Standard Deviation problem » 2011-10-20 21:45:20
- sparkeeuk
- Replies: 7
Hi, I wondered if someone on here could kindly help with one of my maths questions for my course as I can't seem to get my head round this and am hopin someone could put me in the right direction if possible, heres the question.......
The Lengths of pins produced by a machine follow a normal distribution with mean of 2.54cm and a standard deviation of 0.04cm. A pin is rejected if the length is less than 2.44cm or more than 2.60cm
a) What is the percentage of pins accepted
b) If it is decided that 2.5% of the pins are to be rejected because they are too short and 2.5% because they are too long, what is the new range of acceptable lengths
Would really appreciate any help on this
Pages: 1