Question: Jackie spends 8 hours working, 3 hours of exercise and spends 8 hours of sleep per day. How much free time does Jackie have?
Answer with step-by-step thinking: Jackie spends a total of 8 + 8 + 3 = 19 hours on work, exercise, and sleeping. Therefore he has 24 - 19 = 5 hours of free time.
So the answer is 5.


Question: John sells 20 woodburning for $15 each. The wood cost $100. How much does he make in profit?
Answer with step-by-step thinking: He sells the woodburning for 20 * 15 = $300. So he makes a profit of 300 - 100 = $200.
So the answer is 200.


Question: In a factory, there are 3 machines working 23 hours a day. The owner decided to buy a fourth machine, which works only 12 hours a day. One machine can produce 2 kg of material every hour. The factory sells the produced material for $50 per 1 kg. How much can this factory earn in one day?
Answer with step-by-step thinking:

Show your work and conclude with the exact phrasing "Therefore, the final answer is [answer]." where [answer] is just the final number or expression that solves the problem.
user
The total runtime for the first three machines is 3 machines * 23 hours / day / machine = 69 hours / day. So these machines could produce 69 hours / day * 2 kg / hour = 138 kg / day. The fourth machine could produce 12 hours / day * 2 kg / hour = 24 kg / day of material. In total all the machines would produce 138 kg / day + 24 kg / day = 162 kg / day of material. The factory would therefore earn 162 kg / day * $50 / kg = $8100 / day.
So the answer is 8100.