Below is an instruction that describes a task. Write a response that appropriately completes the request in Thai. Please answer in Thai.

### Instruction:
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?

### Response:
 ให้ x เป็นจำนวนข้อคำถามจริงเท็จ
ข้อคำถามต้องเขียนตอบ: x+7
ข้อคำถามปรนัย: 2(x+7)=2x+14
รวมทั้งหมด: x+x+7+2x+14=45
4x+21=45
4x=24
x=<<6=6>>6 ข้อคำถามจริงเท็จ