A sentence saying one group is a percent of another signals a part-whole relationship. Identify the entire group, then put its unknown size after “of” in a Desmos regression. The whole is the group the percent is taken of. Multiplying the known part by the percent finds a smaller part, not the total.
Hints
- Hint 1
The whole is the group that counts as . Here, all employees make up that group. Do the volunteers make up the whole, or only part of it?
- Hint 2
In a percent relationship, the part equals the percent of the whole. Put the unknown total after “of” and the known volunteer count on the other side of the equation.
Step-by-step
Approach 1: Write a percent equation and solve in Desmos
Step 1Put the total after “of”
Let be the whole, all employees at the company. The volunteers are the part, and they make up of the whole, so:
Taking of would treat the volunteers as the whole instead of finding the company’s total.
- Step 2
Find the unknown total
Type . In a regression, Desmos uses for the unknown and to find a value that makes the relationship true. Under PARAMETERS, it shows . So the company has 325 employees in total. Grid in 325.
Approach 2: Think in fifths
Step 1Turn the percent into a fraction
A percent means out of , so . The volunteers are one of five equal groups that together make up all employees.
- Step 2
Count all five groups
Each group has employees. Multiply by five groups:
So the company has employees in total. Grid in 325.