A statement like gives an input-output pair: the number inside parentheses goes in, and the number after the equals sign comes out. Match each number to what the function counts, then put them together in a sentence. Watch for choices that turn a total into a cost per item or a change in cost.
Hints
- Hint 1
In function notation, the number inside parentheses is the input. Here stands for a shirt count. What does the 30 inside count?
- Hint 2
The number after the equals sign is the output. The problem defines as total cost in dollars. Does describe the whole batch, one shirt, or a change in cost?
Step-by-step
Read the input and output in context
Step 1Identify the input
No Desmos needed. The function value is already given, so there’s nothing to calculate.
A function’s input is the number inside its parentheses: replaces , so it means 30 shirts produced. It doesn’t mean 30 more shirts; no previous count is given.
- Step 2
Identify what the output measures
A function’s output is the number after the equals sign, so is the value of . The problem says measures total cost in dollars, so that’s $540 for the whole batch, not $540 for each shirt.
- Step 3
Put the pair into a sentence
Pair the input with the output: means producing 30 shirts costs $540 in total. Choice C.