A known total split between two ticket types can become a one-variable equation: if tickets are one type, the rest are the total minus . Multiply each count by its own price, set the sum equal to the money collected, and use a Desmos regression to solve. Don't use the total ticket count as the student count too; that counts adult tickets twice.
Hints
- Hint 1
Let count adult tickets. The two ticket counts must add to , so the student count is what's left after taking away . How would you write that count?
- Hint 2
Each revenue term is a price multiplied by the number of tickets sold at that price. Keep the $6 price with adults and the $4 price with students, then add the two amounts to get the total collected.
Step-by-step
Approach 1: Write one equation and solve in Desmos
- Step 1
Write the student count
Let be the number of adult tickets. All tickets are either adult or student tickets, so the student count is the total minus the adult count:
- Step 2
Write the money equation
Adult sales bring in dollars, and student sales bring in dollars. Their sum is the $400 collected: . Don't put in place of : the already includes the adult tickets.
- Step 3
Solve for the adult count
Type in Desmos. Use instead of so Desmos solves for a number rather than graphing with ; tells it to match the two sides. Under PARAMETERS, it shows . Since counts adult tickets, the club sold adult tickets. Choice B.
Approach 2: Count the extra money from adult tickets
- Step 1
Find an all-student starting total
Imagine all tickets cost the student price of $4. The sales total would be:
- Step 2
Find the money above that starting total
Subtract that starting total from the actual sales of $400: . Adult tickets account for this extra $80.
- Step 3
Find the extra money per adult ticket
Each adult ticket replaces one $4 student ticket with a $6 ticket, so find the price difference: . Each adult ticket adds $2 to the starting total, not $4.
- Step 4
Count the adult tickets
Divide the extra $80 by the $2 added per adult ticket: . The club sold adult tickets. Choice B.