Answer:
Felix's third test score must be greater than 94
Step-by-step explanation:
Felix scores on Sociology 212 tests:
1st test - 52
2nd test - 64
3rd test - x
Find the average of Felix's scores:
[tex]\text{Average}=\dfrac{\text{The sum of all scores}}{\text{The total number of scores}}\\ \\\text{Average}=\dfrac{52+64+x}{3}[/tex]
An average of the three test must be above 70, this means
[tex]\text{Average}>70\\ \\\dfrac{52+64+x}{3}>70[/tex]
Solve this inequality. First, multiply it by 3:
[tex]52+64+x>210\\ \\x>210-52-64\\ \\x>94[/tex]