A certain basketball team played seven games and scored an average of

Answer = D. 86

Score of remaining 2 teams = 80*7 - (75+69+81+90+73) = 172

Average \(= \frac{172}{2} = 86\)

The first thing to recognize is that to find the average, you take the sum and divide by the number of inputs (games, in this case) you have. Here were have 7 inputs, or games. Therefore, I approach this problem by first writing the following:
(A+B+C+D+E+F+G)/7 = 80
Plug in the sum of the first 5 games (388) for (A+B+C+D+E)
[(388+F+G)/7]= 80
Multiply both sides by 7
388+F+G = 560
Subtract 388 on both sides
F+G = 172
Since the answer asks for the average of the last two games, F and G, all you need to do is take 172 and divide it by 2, giving 86. This is the tricky part of thi sproblem, because if you do not read carefully you will end up trying to figure out what F and G are, and not what the average of the two is.

The answer is D.

OFFICIAL SOLUTION:

(D) Let’s use x to denote the total number of points scored in the last 2 games. Because the average number of points scored per game equals the sum of all points scored divided by the number of games, we can set up the following equation:
80 = (75 + 69 + 81 + 90 + 73 + x)/7
80 = (388 + x)/7
560 = 388 + x
x = 172.

The question asks for the average score over the last two games, which is:
172/2 = 86.

The correct answer is choice (D).

Total points scored by the basketball team = 80 * 7 = 560 points
Total of first 5 games = 75 + 69 + 81 + 90 + 73 = 388 points
Total of points for last 2 games = 560 - 388 = 172 points
Average for last 2 games = 172 / 2 = 86 points
correct answer - D

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