Question 981265
To bring her average test score up to 80 percent, Melissa needs to score 95 percent on her fifth test in history.
 What was the total score for the first four tests that she took?
:
Let x = total score for the first 4 tests
:
{{{((x + 95))/5}}} = 80
Multiply both sides by 5
x + 95 = 400
x = 400 - 95
x = 305 is total of the first 4 tests. (An average of 305/4 = 76.25)