We have that
Cost use of a backhoe----------------------$300 an hour
Estimate for equipment rental each week---------------------$18,400
Total hours operator per week--------------------------------------40
40*300=$12000---------------------it is the cost per week to use a backhoe
$12000<$18400 is ok
The maximum of hours that I can rent a backhoe are 40 hours, since it is the limit of the operator and it do not overcome the total budget