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    So I'm not really sure how to answer this question on normal distributions:
    the lifetime of an electrical component may be modelled by a normal distribution with mean 2500 hours and a varience 900 hour^2.
    How long would you expect 35% of the components to last?
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    p(X>x)=0.35
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    So do I just use the tables once I've standardised it?
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    (Original post by phoebeg76)
    So do I just use the tables once I've standardised it?
    Yes
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    (Original post by morgan8002)
    Yes
    Okay thank you! I wasn't sure if there was some sort of long technique or something
 
 
 
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