So the cable installer charges 52.50 an hour. meaning you would multiply that by whatever amount of hours he will work. so 52.50 times 4.5 hours equals $236.25. Now he also charges an extra fee for the service, So we add 75 dollars onto that making it $311.25.
If you want it in formula form here you go
y represent total amount in the end and x equals amount of hours
y=52.50x + 75
y = 52.50(4.5) + 75
y = 236.25 + 75
y = 311.25