Answer to Question #199103 in Statistics and Probability for mandona

Question

The weights (to the nearest tenth of a kilogram) of 30 students were measured and recorded as follows: 59.2, 61.5, 62.3, 61.4, 60.9, 59.8, 60.5, 59.0, 61.1, 60.7, 61.6, 56.3, 61.9, 65.7, 60.4, 58.9, 59.0, 61.2, 62.1, 61.4, 58.4, 60.8, 60.2, 62.7, 60.0, 59.3, 61.9, 61.7, 58.4, 62.2 Prepare an ordered stem and leaf plot for the data. Briefly comment on what the analysis shows.

Answer 1

The stems will be whole number values and the leaves will be the decimal values.

The data ranges from 56.3 to 65.7 so the stems should start at 56 and finish at 65.

It is not necessary to split stems because the leaves are not crowded on too few stems; nor is it necessary to round the values as the range of values is not large. The stem plot reveals that the group with the highest number of observations recorded is the 61 to 61.9 group.

Outliers are 56.3 and 65.7, as these two values are quite different from the other values.

By ignoring these two outliers, the previous example’s stem plot could be redrawn as below:

Outliers: 56/3 and 65/7