Give an example of a relation in real life, and explain why it is a function.

One example of a relation in real life that is also a function is the relationship between a person's age and their height. In this case, the input (age) is being mapped to a single output (height).

This relation is a function because for a given age, there is only one corresponding height. Each age has a unique height associated with it, and there are no instances where one age can have multiple heights. For example, if a person is 10 years old, their height may be 4 feet 8 inches. This height is specific to their age and will not change. Therefore, for every age, there is a unique and consistent height, making the relation a function.

One example of a relation in real life that is also a function is the relationship between a student's grade and their percentage score on a test.

In this case, each student's grade corresponds to a specific percentage score. For example, if a student scores 85% on a test, the corresponding grade might be a B. This relationship meets the criteria for a function because each input (percentage score) maps to a unique output (grade).

There is only one grade associated with each percentage score, and no two students with different percentage scores will receive the same grade. This ensures that for every possible input (percentage score), there is a definite output (grade), making it a function.

One example of a relation in real life is the relationship between a person's age and their height. This is a function because for each age, there is only one corresponding height. When we plot the ages on the x-axis and the heights on the y-axis, each age value would have exactly one height value associated with it. For instance, if we consider a 10-year-old child who is 130 cm tall, there wouldn't be another height value associated with the age of 10. Therefore, this relation satisfies the criteria for a function as it exhibits a unique output for each input.