Brenda's scores on the first three of four 100-point science tests were 95, 92, and 89. What score does she need on her fourth science test to ensure an average score of at least 93?
Brenda has scored relative to her desired average +2, -1, and -4 points, or a total of -3 points. To ensure her average is 93, she must score at least 3 points above her desired average: 96 or better.
