The Normal distribution with mean μ = 6.8 and standard deviation σ = 1.6 is a good description of the Iowa Test vocabulary scores of seventh grade students in Gary, Indiana. This is a continuous probability model for the score of a randomly chosen student.
(a) Write the event "the student chosen has a score of 10 or lower" in terms of X.
(b) Find the probability of an event which represents "the student chosen has a score of 10 or lower".
(a) Write the event "the student chosen has a score of 10 or lower" in terms of X.
(b) Find the probability of an event which represents "the student chosen has a score of 10 or lower".
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a) x <= 10
b) P(x <= 10) = P(z < (10 -6.8)/1.6) = P(z < 2) = 0.9772
b) P(x <= 10) = P(z < (10 -6.8)/1.6) = P(z < 2) = 0.9772