Answer:
84 is the score that you Russell needs on the next test to achieve an average of at least 80.
Step-by-step explanation:
Russell's test scores are: 70,74,87 and 85
Average of the test scores = A = 80
Let thescore needed to achieve an average of 80 be x
Average = [tex]\frac{\text{Sum of terms}}{\text{Number of terms}}[/tex]
[tex]A=\frac{70+74+87+85+x}{5}[/tex]
[tex]80=\frac{70+74+87+85+x}{5}[/tex]
[tex]70+74+87+85+x=400[/tex]
[tex]x=400-(70+74+87+85)=84[/tex]
84 is the score that you Russell needs on the next test to achieve an average of at least 80.
