Question

rainfall (mm)
stem|leaf
3|8 9
4|1 2 6
5|1 5 6 9
6|0 1 3 4 6
7|0 6 8
8|1 6
key: 6|0=60
how many days had less than 40 mm of rainfall?

Explanation:

Step1: Identify the relevant rows

We look at rows with stem 3 as values in this row are in 30 - 39 range.

Step2: Count the number of data - points

In the row with stem 3, there are 2 data - points (38 and 39).

Answer:

2