Answer:
88
Step-by-step explanation:
[tex] \frac{86 + 94 + 88 + 95 + 89 + x}{6} = 90[/tex]
The mean would be the sum of all the math quiz grades divided by the number of quizzes taken.
Solve for x:
[tex]86 + 94 + 88 + 95 + 89 + x = 540[/tex]
[tex]452 + x = 540[/tex]
[tex]x = 88[/tex]
Thus, Allen needs at least an 88 to obtain a mean of at least 90.