Final answer:
The mode is the number that appears most frequently in a set of numbers. For the given list, the mode is 30, as it is the only number that appears more than once.
Step-by-step explanation:
The mode of a set of numbers is the number that appears most frequently in the set.
To find the mode of the given numbers 19, 30, 30, 32, 46, 49, 51, 73, we need to identify which number appears most often.
In this list, the number 30 appears twice, while all the other numbers appear only once.
Therefore, the mode of the numbers 19, 30, 30, 32, 46, 49, 51, 73 is 30.