Beginning Algebra With Applications, Chapter 5, 5.5, Section 5.5, Problem 10

The following table shows the length of the humerus (the long bone from the shoulder to the below), in centimeters, and the total wingspan, in centimeters, of several pterosaurs, which are extinct flying reptiles of the order Pterosauria. Write a relation in which the first coordinate is the length of the humerus and the second coordinate is the wingspan. Is the relation a function?

$\begin{array}{c|ccccccc} \text{Length of humerus, in centimeters} & 24 & 32 & 22 & 15 & 4.4 & 17 & 15 \\ \hline \\ \text{Wingspan, in centimeters} & 600 & 750 & 430 & 300 & 68 & 370 & 310 \end{array}$

The table can be written as the relation

$\{ (24,600), (32,750), (22,430), (15,300), (4.4, 68), (17,370), (15,310) \}$

The relation is a function because no two ordered pairs have the same first coordinate and different second coordinates.