Jane is taking a class and asks you to help her figure out what her last grade must be in the class to get a 85 in the class. She tells you the following calculation is used to find your final grade:

Question

75+85+90+X
___________ >

4

x is her last score which has not been taken. Explain this equation and the process you would use to solve for the unknown test score. Solve for the test score.

Answer 1

4 X 85 = 340

75+85+90+ X= 340
250 + X= 340
X=90