(a+b+c)/3 = 40
        a+b+c = 120
 The sum of a, b, and c is 120.  To figure out the average of a, b, c, and 39:
        (a+b+c+39)/4 = (120+39)/4 = 39.75, which is less than 40.  The answer is B.

Back to Red Answer Sheet

Back to Answer Sheet