l Given scores of 81,83,87,89, what should the next score be in order t

Enter Scores Comma Separated)

Enter Average


Given 4 scores of 81, 83, 87, 89:

what should be score number 5
in order to attain an average score of 88?

Setup Average Equation:

Average  =  Sum of our 4 numbers + unknown score of x
  Total Numbers

88  =  81 + 83 + 87 + 89 + x
  5

Cross Multiply

81 + 83 + 87 + 89 + x = 88 x 5

x + 340 = 440

Subtract 340 from both sides of the equation to isolate x:

x + 340 - 340 = 440 - 340

Final Answer


x = 100