Normal Distribution help @beautiful_gurl
The time required to finish a test in normally disrtibuted with a mean of 40 minutes and a standard deviation of 8 mins. What's the probability that a student chosen at random will finish the test in more than 48 mins?

Question

Normal Distribution help @beautiful_gurl 
The time required to finish a test in normally disrtibuted with a mean of 40 minutes and a standard deviation of 8 mins. What's the probability that a student chosen at random will finish the test in more than 48 mins?

anonymous · Answer

Choices are:
84%
2%
34%
16%

anonymous · Answer

@MrDoe ha you gonna try to help me again :) lol

anonymous · Answer

but I have to leave so I was just putting that up there for later!

mrdoe · Answer

sure, did you guys talk about bell curves and the standard deviation yet?

anonymous · Answer

I have a WHOLE quiz of that.. ready to get help on

anonymous · Answer

um, we did the standard deviation, I have NO idea what bell curves are

mrdoe · Answer

ok, well the short version is that is we usually use sigma to represent the standard deviation, and +/- one sigma from the average yields a probability of 68.3%, so since it can only be in the positive (+sigma) that would be half of 68.3=about 34%

anonymous · Answer

attachment

anonymous · Answer

@Argos yeah I hate that thing

anonymous · Answer

oh yeah I'm horrible at this stuff

anonymous · Answer

well I have to go my mom's back, but I'll be on later tongith!

anonymous · Answer

plug in values this should be easy problem

anonymous · Answer

@Argos Yeah but I just don't understnad it at all

mrdoe · Answer

gaussian distribution gets complex fast so dont worry about it :)

anonymous · Answer

each Standard deviation is 8minutes and the center of the bell curve is 40

and you are looking for the probability > 48

anonymous · Answer

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