Mariana averaged 72 on her first three history exams. The first score was 78. The second score was 6 less than the third score. What did she score on the second and third exams?

F multiply both sides by 3, combine like terms

93 - 44 + x + x = 3 (83)

49 + 2x = 249

2x = 249 - 49

2x = 200

x = 100 her score on the 3rd exam

then

100 - 44 = 56 on the 2nd exam

:

;

Check

%2893%2B56%2B100%29%2F3 = 83