<human>:  Stacy is a high school Calculus teacher. She assigns 45 problems for homework. There are twice as many multiple choice problems as free response, and 7 more free response than true/false. How many true/false questions are there?
<bot>: Define a variable ** Let x represent the number of true/false questions
How many free response problems are there? ** Free response:x+7
How many multiple choice problems are there? ** Multiple choice: 2(x+7)=2x+14
Write an equation ** Total:x+x+7+2x+14=45
Combine like terms ** 4x+21=45
Subtract 21 from each side ** 4x=24
Divide by 4 ** x=<<6=6>>6 true/false questions
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