Question

In: Statistics and Probability

In a city with three high schools, all the ninth graders took a Standardized Test, with...

In a city with three high schools, all the ninth graders took a Standardized Test, with these results:

High School Mean score on test Number of ninth graders
Glenwood 79 280
Central City 94 348
Lincoln High 66 151

The city's PR manager, who never took a college math class, claimed the mean score of all ninth graders in the city was 79.7 . Of course, that is incorrect. What is the mean score for all ninth graders in the city?

Round to one decimal place.

Mean of all ninth grader's scores =

To compute a student's Grade Point Average (GPA) for a term, the student's grades for each course are weighted by the number of credits for the course. Suppose a student had these grades:
3.7 in a 5 credit Math course
2.1 in a 2 credit Music course
3.0 in a 5 credit Chemistry course
3.0 in a 6 credit Journalism course
What is the student's GPA for that term? Round to two decimal places. Student's GPA =

To compute a student's Grade Point Average (GPA) for a term, the student's grades for each course are weighted by the number of credits for the course. Suppose a student had these grades:
3.9 in a 5 credit Math course
2.0 in a 2 credit Music course
2.8 in a 5 credit Chemistry course
3.4 in a 4 credit Journalism course
What is the student's GPA for that term? Round to two decimal places. Student's GPA =

Every year, the students at a school are given a musical aptitude test that rates them from 0 (no musical aptitude) to 5 (high musical aptitude). This year's results were:

Aptitude Score Frequency
0 4
1 3
2 2
3 1
4 5
5 1



The mean (¯xx¯) aptitude score:  (Please show your answer to 1 decimal place.)

The median aptitude score:

The mode aptitude score:  (Please separate your answers by ',' in bimodal situation. Enter DNE if there is no mode.)

The Acme Company manufactures widgets. The distribution of widget weights is bell-shaped. The widget weights have a mean of 57 ounces and a standard deviation of 6 ounces.

a) 95% of the widget weights lie between  and

b) What percentage of the widget weights lie between 39 and 69 ounces?  %

c) What percentage of the widget weights lie below 63 ?  %

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