math
posted by Anonymous on .
An employment agency requires applicants average at least 70% on a battery of four job skills tests. If an applicant scored 70%, 78%, and 82% on the first three exams, what must he score on the fourth test to maintain a 70% or better average?

4 * 70% = 280
70 + 78 + 82 = 230
280  230 = 50