MHB -aux.06.normal distribution to standard distribution

AI Thread Summary
The discussion focuses on converting a normal distribution to a standard distribution using z-scores. The calculations involve determining z-scores for specific values, with results showing probabilities using a z-table. The first part calculates P(.70<X) as 0.8413 and P(.70<X<.79) as 0.5328. The second part approximates a value c related to a 3% probability, resulting in c being approximately 0.65. Overall, participants confirm the calculations and emphasize the value of seeking assistance.
karush
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so for (a) (i) I used $\frac{x-\mu}{\sigma}=z
$\dfrac{0.70-0.76}{0.06}=-1 = a $ and $\frac{0.79-0.76}{0.06}=.5 = b$
ii $P(.70<X)$ z-table for $-1$ is $0.3413$ so $0.3413 + .500 = 0.8413$
$P(.70<X<.79)$ z-table for $.5$ is $0.1915$ so $0.3413+0.1915=0.5328$
 
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Looks good so far! (Sun)
 
(b) (i)
View attachment 1139

(ii) z-table for $3\% \approx -1.88$

so $\frac{c-0.76}{0.06}=-1.88$ thus $c\approx 0.65 s$

my shaky attempt at this anyway(Wasntme)
 
Again, looks good! (Clapping)
 
MarkFL said:
Again, looks good! (Clapping)

well, it definitely pays to ask for help...:cool:
 
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