Set alot more than the orders, if they get alot of extra male, most are sold , even given as a bonus as extra chick when you buy 100. At least I know a few do.
Sure they know its a 50 to 50 odds. Any way they alway set alot more eggs than orders. I can pick up extra cockerel ,cheaper than hatching eggs.
They really do.. The farm store that I frequent orders 300 per week from ideal, they generally get 400 in with 100 of them being males.. packing peanuts. They give the ones that survive the voyage to anyone whom buys pullets and wants a rooster or two.
They'll have a pretty fair idea of what the hatch percentage will be for the eggs they are using so for example if they want 400 pullets and their hatch rate is 80% they'll set a thousand eggs or more likely a 1050 just to be sure they get the needed 400 pullets.