1 The national average for the math portion of the College B

1] The national average for the math portion of the College Board’s SAT is 513 with a standard deviation of 92. The median is 546.The national average for the math portion of the College Board’s SAT is 513 with a standard deviation of 92. The median is 546. (Make sure you carry all decimals until you reach your answer, then round to four decimals)

A] (Skewed right,Skewed right, Mounted-Shaped, Symmetrical)       Because   (Blank) (<,=,>)   (Blank)

B] (Chebyshev\'s,Empirical) rule predicts that (at least 75,at least 88.8889,about 68,about 95,about 99.7) percent of the SAT math score data should lie.

C) between a 329 and a 697 ,which are +/- (Blank) standard deviation(s) away from the mean.

Please need help how to solve these equations, and answer for blank and ().

Solution

a)

SKEWED LEFT, because Mean < Median. [ANSWER]

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b)

k = (x - u) / sigma

hence, for x = 697,

k = (697 - 513)/92 = 2 standard deviations

Hence,

1 - 1/k^2 = 1 - 1/2^2 = 0.75 or 75%.

Hence,

CHEBYSHEV\'S RULE predicts that AT LEAST 75 percent of the SAT math score data should lie between a 329 and a 697 ,which are +/- 2 standard deviation(s) away from the mean. [ANSWER]