Assume the sample below is a perfectly random sample of students at a school. How much greater is the mean of the reported heights at the school than the mean of the actual, measured heights at the school?
Number Reported height Measured Height Difference
Description
1
61
62
-1
Under reported
2
68
68
0
Accurately reported
3
57.5
56.5
1
Over reported
4
48.5
47
1.5
Over reported
07
75
72
3
Over reported
6
65
65
O
Accurately reported
7
80
78
2
Over reported
8
68
67
1
Over reported
9
69
69.5
-0.5
Under reported
10
63
62.5
0.5
Over reported

0.75

Step-by-step explanation:

The table is not well presented (See Attachment)

There are at least two approaches to this question

Method 1:  

Steps

1. Calculate the mean of reported heights

Mean of reported heights = (61+68+57.5+48.5+75+65+80+68+69+63)/10

Mean of reported heights = 655/10

Mean of reported heights = 65.5

2. Calculate the mean of measured heights

Mean of measured heights = (62 + 68 + 56.5 + 47 + 72 + 65 + 78 + 67 + 69.5 + 62.5)/10

Mean of measured heights = 647.5/10

Mean of measured heights = 64.75

3. Get their difference

Difference = Mean of reported heights - Mean of measured heights

Difference = 65.5 - 64.75

Difference = 0,75

Method 2: Calculate the mean of their difference

Mean of difference = Sum of difference / Number of observations

Mean of difference = (-1 + 0 + 1 + 1.5 + 3 + 0 + 2 + 1 – 0.5 + 0.5)/10

Mean of difference = 7.5/10

Mean of difference = 0.75

Note that in both cases, the result is 0,75.

Hence, the reported heights at the school is 0.75 greater than the actual measured height

the results from a pre-test for students for the year 2000 and the year 2010 are illustrated in the box plot. what do these results tell us about how students performed on the 29 question pre-test for the two years?

if we compare only the lowest and highest scores between the two years, we might conclude that the students in 2010 did better than the students in 2010. this conclusion seems to follow since the lowest score of 8 in 2010 is greater in value than the lowest score of 6 in 2000. also, the highest score of 28 in 2010 is greater in value than the highest score of 27 in 2000.

but the box portion of the illustration gives us more detailed information. the middle bar in each box shows us that the median score of 20 in 2000 is greater in value than the median score of 17 in 2010. further, we note that the box and whiskers divide the illustration into four pieces. each of these four pieces represents the same portion of students. so, the upper half of the students in 2000 scored in the same score range as the upper one-fourth of the students in 2010, see the illustration at a score of 20.

by considering the upper one-fourth, upper half, and upper three-fourths instead of just the lowest and highest scores, we would conclude that the students as a whole did much better in 2000 than in 2010. we would conclude that as a whole the students in 2010 are less prepared than the students in 2000.

in this section, we discuss box-and-whisker plots and the five key values used in constructing a box-and-whisker plot. the key values are called a five-number summary, which consists of the minimum, first quartile, median, third quartile, and maximum.

step-by-step explanation: