Ralph pays his workers $ 100 each, and labor is the only variable cost. At a quantity of 5000 chickens, how many workers does he hire?

He hires 8 workers

Explanation:

The total cost is $1600 for 5,000 chickens minus the fixed cost of $800, which equals $800. The total cost is total of fixed cost and variable cost as in absence of production the total variable cost is zero so from this we can conclude that total fixed cost is zero.

Then divide the total variable cost ($800) buy what Ralph pays his workers ($100), which comes to 8.