Final answer:
Kelby has several pets including birds, snakes, and spiders. An expression like x + y + z, where each letter represents the quantity of each type of pet, can be used to determine the total number of pets she has.
Step-by-step explanation:
Based on the information provided about the Kayapó and their pets, let's create a similar scenario for Kelby. Let's say Kelby has several pets. She has birds, snakes, and spiders. The expression x + y + z represents the total number of pets Kelby has, where x is the number of birds, y is the number of snakes, and z is the number of spiders.
For example, if Kelby has 5 birds, 3 snakes, and 2 spiders, the expression for the total number of pets she has would be 5 + 3 + 2. Adding those numbers together, Kelby would have a total of 10 pets. This example shows how we can use basic algebra to represent real-life quantities and practice addition.