In the stemandleaf display below answer the following questi

In the stem-and-leaf display below answer the following questions?

Stem

Leaf

5

9

6

3 3 5 8 8

7

0 0 2 3 4 6 7 7 8 8 9

8

1 2 7

9

0 7 7

10

7

11

3 6 8

stem = ones place, leaf = tenths place (first place to the right of the decimal)

a.) What appears to be a representative sterngth value? Do the observations appear to be highly concentrated about the representative value or rather spread out?

b.) Does the display appear to be reasonably symmetric about a representative value, or would you describe its shape in some other way?

c.) Do there appear to be any outlying strength values?

d.) What proportion of strength observations in this sample exceed 10MPa?

Solution

From the data given in the stem plot let us find the central tendency, mean , median and mode

Mean = 81.407

Median = 77

Mode:63, 68, 70, 77, 78, 97

We find that it is concentrated around median or mode but not mean.

b) Not reasonably symmetric and it is not unimodal.

c) outliers are 59, 113,116, 118

d) 4/27 = 0.1481 proportion