Question

What system of equations would you use to solve the problem below?

A test is worth 100 points. Multiple-choice questions are worth 3 points and
short-answer questions are worth 5 points. If the test has 28 questions, how
many multiple-choice questions are there?

Answer 1

Let x be multiple-choice questions
Let y be short-answer questions

x + y = 28

3x + 5y = 100