Question 66385
Your test score are 75, 93, 90, 82, and 85. What is the lowest score you can obtain on the next test to achieve an average of at least 86?
:
Call the 6th test score x, write an average equation:
:
{{{((75 + 93 + 90 + 82 + 85 + x))/6}}} => 86
:
{{{((425 + x))/6}}} => 86
:
Get rid of the denominator, mult eq by 6
425 + x => 6(86)
425 + x => 516
x => 516 - 425
x => 91
:
You can check it by adding up all 6 grades, which include 91, and dividing by 6.