SOLUTION: This is the question: Over the past ten years, a high school Spanish teacher has been giving the same comprehensive final examination to all students in first-year Spanish. The

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Question 913237: This is the question:
Over the past ten years, a high school Spanish teacher has been giving the same comprehensive final examination to all students in first-year Spanish. The mean of this examination is 78.4 and the standard deviation is 14.8. To pass the course, a student must score at least a 55.
(a) What is the probability that a randomly selected student earns a score that is greater than the minimum passing score? Include a sketch of the normal curve for this.
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
z+=blue+%28x+-+78.4%29%2Fblue%2814.8%29
re TY:
P(x > 55) = normalcdf(-1.5811, 100)= .9431 is the straight forward approach (not using 1-P( x ≤ 55)
...........
P( x> 55)= 1 - P( z < -23.4/14.8) = 1 - normalcdf(-100, -1.5811) = 1 - .0569 = .9431 0r 94.31%
0r
P(x > 55) = normalcdf(-1.5811, 100) is the straight forward approach:
.........
P( x> 55) Area to the Right of z = -1.5811
the x-axis are z-scores from -5 to 5