Question 91692
 need help defining a variable, writing and solving this inequality:
Ray had scores of 75,82,94, and 77 on his first four science tests. What must he score on the next test to have an average of at least 85?
:
Let x = the score required on the 5th test to have at least an 85 average:
:
{{{((x + 75 + 82 + 94 + 77 ))/5}}} => 85
 
{{{((x + 328))/5}}} => 85
:
Multiply equation by 5 and you have:
x + 328 => 5(85)
:
x + 328 => 425
:
x => 425 - 328
:
x => 97 required
:
:
Check on calc: (97+75+82+94+77)/5 = 85