A company is hired to do landscaping work in suburban neighborhoods during the summer. If they buy expensive machinery, then they can hire fewer workers to produce the same output. Over the course of the summer, they need to finish landscaping work at 50 houses. To perform this job, they have 3 possible combinations of output they can use:

Method 1: 20 workers, 10 machines

Method 2: 50 workers, 2 machines

Method 3: 100 workers, 0 machines

Method 4: 10 workers, 12 machines

Hiring a worker for the summer costs $10. Each machine costs $100. Which method should they use?