Chapter 2 - Methods for Describing Sets of Data - Exercises 2.22 - 2.43 - Learning the Mechanics - Page 45: 2.27a

$23$

In a stem-and-leaf display, each numerical data item is split into two parts. The last digit of the data item is called the leaf, while all the leading digits make up the stem. Leaves with the same stem are written one after each other in the same row. Thus, there are as many observations as there are leaves: $1+3+5+7+4+3=23.$