You are taking a course that has four tests. The first three tests are worth 100 points

Question:

You are taking a course that has four tests. The first three tests are worth 100 points each and the fourth test is worth 200 points. To get an A in the course, you must have an average of at least 90% on the four tests. Your scores so far are 87, 92, and 84. What must you score on the fourth test to get an A in the course?