We will divide the earnings with the time needed to work to earn that money .
Melanie : 97.5 ÷6=16.25
Earl: 296 ÷20=14.8
So Melanie earns $16.25 per hour,while Earl earns $14.8 per hour
Since 16.25 >14.8,Melanie earns more per hour
(Hope this helped)