posted by seano .
Sam must have an average of 70 or more in his summer course to obtain a grade of C. His firs three test grades were 75,63, and 68. Write an inequality representing the score that Sam must get on the last test to get a C grade.
70 = (75+63+68+x)/4 ...with x being what he must get.
So you solve that:
70(4)-75-63-68 = x
x = 74
So therefore, Sam must get a 74 or above to get a C grade.
x => 74