Answer:
 $1769.06
Step-by-step explanation:
The sum of Mia's three highest salaries is ...
 $92,000 +94,800 +96,250 = $283,050
so the average is ...
 $283,050/3 = $94,350
Her pension is then ...
 0.01875 × $94,350 = $1769.06
_____
Additional comment
This is equivalent to the total of those salaries, divided by 160.
 T/3 × 0.01875 = T × (0.01875/3) = T × 0.00625 = T/160
Sometimes, there are simpler ways to calculate things like this.