Answer:
58mph
Step-by-step explanation:
Given:
Each mph over the speed limit gets fined $10
or mathematically, rate of fine = $10/mph
also, total fine was $80.
Number of mph over the speed limit,
= total fine ÷ rate of fine
= $80 ÷ $10/mph
= 8 mph.
Given that the speed limit was 50 mph, Cathy's final speed,
= speed limit + number of mph over speed limit
= 50 + 8
= 58 mph