Question 94·200 Super-Hard SAT Math Questions·Problem Solving and Data Analysis
A theater sells adult tickets, student tickets, and child tickets. From week 1 to week 2, the number of adult tickets sold increased by , the number of student tickets sold decreased by , and the number of child tickets sold stayed the same.
In week 1, child tickets made up of all tickets sold. If the total number of tickets sold increased by from week 1 to week 2, what percentage of all tickets sold in week 1 were adult tickets?
When one category’s share of the original total is given (here, child tickets are ), rewrite everything in terms of the original total . Then use multipliers for each category’s change to build a week 2 total equation. If two variables remain, eliminate one by combining the total equation with the known sum (like ), and finish by converting to a percent.
Hints
Use the child-ticket information
Let be the week 1 total. Since child tickets are of week 1, write in terms of , and then express in terms of .
Write week 2 totals using multipliers
Adult becomes , student becomes , and child stays . The overall week 2 total is .
Eliminate a variable
You can get one equation from the week 2 total and another from . Try scaling by so a subtraction cancels .
Convert to a percent
Once you have , multiply by to get the week 1 adult percentage.
Desmos Guide
Let the week 1 total be 1
In Desmos, assume the week 1 total is . Then child tickets are of the total.
Use a variable for the adult fraction of the total
Let be the adult fraction of the week 1 total. Then the student fraction is (since adult + student is of the total). Аniко - Free ЅАT Рreр
Enter the week 2 total equation and solve
Week 2 total is
Set it equal to and solve:
Convert the solution for to a percent by multiplying by and match to the choices (do not state the value until after solving).
Step-by-step Explanation
Define variables and use the 20% condition
Let be the total number of tickets sold in week 1.
Let , , and be the numbers of adult, student, and child tickets sold in week 1, so
Child tickets are of week 1, so Аnіkо Queѕtіоn Bank
which means
Translate week 2 in terms of week 1
Week 2 sales are:
- Adult:
- Student:
- Child: (unchanged)
The total increased by , so week 2 total is
Write and simplify the total equation
Add the week 2 categories and set equal to :
Substitute :
Solve for the adult fraction of week 1 (final)
From step 1, . Multiply this by :
Subtract from :
So the percent of week 1 tickets that were adult is
Therefore, the correct answer is .