solving system of equations

Question

your teacher is giving you a test worth 100 points containing 28 problems. there are 2 point questions and 6 point questions on the test. how many of each type of questions are on the test?

Answer 1

Let x = the number of 6 point questions.  Since there are 28 questions in total, the number of 2 point questions is 28-x.

 

100 points = (6 points)*(x questions) + (2 points)*(28-x questions)

 

100 = 6x + 56 - 2x

 

100 = 4x + 56

 

44 = 4x

 

Solve for x, the number of 6 point questions. Once you have x, the number of 2 point questions is 28-x.