Let:
x = Score of the first test
y = Score of the second test
z = Score of the third test
w = Score of the fourth test
Part A:
[tex]\begin{gathered} Average\ge92 \\ \text{where:} \\ Average=\frac{x+y+z+w}{4} \\ \text{and:} \\ x=85 \\ y=89 \\ z=95 \\ so\colon \\ \frac{85+89+95+w}{4}\ge92 \\ \frac{269+w}{4}\ge92 \end{gathered}[/tex]Part B:
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