document.write( "Question 847367: A final exam in Math 1148 has a mean of 73 with standard deviation 7.8. If a student is randomly selected, what is the probability that his/her test score is at least an 80?
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Algebra.Com's Answer #510373 by ewatrrr(24785)\"\" \"About 
You can put this solution on YOUR website!
 
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document.write( "Hi,
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document.write( "The 9999 is just a 'place holder' so to speak (A Number SO big, relative to the parameters given...
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document.write( "that the 'z' representing it...it is going to be VERY far to the right on the Normal curve 
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document.write( "(See below how far right 3 SDs is)
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document.write( "Using TI Calcuator
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document.write( "The syntax is normalcdf(smaller, larger, µ, σ).
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document.write( "Note: The 9999 is used as the larger value to be at least 5 standard deviations from the mean.
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document.write( "P(x≥ 80) =  normalcdf(80, 9999, 73, 7.8).
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document.write( "Below:  z = 0, z = ± 1, z= ±2 , z= ±3 are plotted.  
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document.write( "Note: z = 0 (x value the mean) 50% of the area under the curve is to the left and %50 to the right
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