8.2. From past experience, a professor knows that the test score of a student taking her final examination is a random variable with mean 75. a. Give an upper bound for the probability that a student's test score will exceed 85. b. Suppose, in addition, that the professor knows that the variance of a student's test score is equal to 25. What can be said about the probability that a student will score between 65 and 85? c. How many students would have to take the examination to ensure with probability at least .9 that the class average would be within 5 of 75? Do not use the central limit theorem.
Angles in Circles
Angles within a circle are feasible to create with the help of different properties of the circle such as radii, tangents, and chords. The radius is the distance from the center of the circle to the circumference of the circle. A tangent is a line made perpendicular to the radius through its endpoint placed on the circle as well as the line drawn at right angles to a tangent across the point of contact when the circle passes through the center of the circle. The chord is a line segment with its endpoints on the circle. A secant line or secant is the infinite extension of the chord.
Arcs in Circles
A circular arc is the arc of a circle formed by two distinct points. It is a section or segment of the circumference of a circle. A straight line passing through the center connecting the two distinct ends of the arc is termed a semi-circular arc.
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![8.2. From past experience, a professor knows that the test score of a student taking her final examination is a random variable with mean 75.
a. Give an upper bound for the probability that a student's test score will exceed 85.
b. Suppose, in addition, that the professor knows that the variance of a student's test score is equal to 25. What can be said about the probability that a student will
score between 65 and 85?
c. How many students would have to take the examination to ensure with probability at least .9 that the class average would be within 5 of 75? Do not use the central
limit theorem.](/v2/_next/image?url=https%3A%2F%2Fcontent.bartleby.com%2Fqna-images%2Fquestion%2F171ff07b-7b62-4691-9b2a-ffaa1328dd79%2F425f8a66-79c7-4295-b975-78a0edc07f94%2Fonglxyf.jpeg&w=3840&q=75)
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