Come up with a question and reasoning that would justify [2900] as the answer.
The question is: Twenty people pre-bought plane tickets at a price of $155 per ticket. Thirty people bought their plane tickets at the gate and they each paid $200 for their ticket. How many more dollars did the people at the gate pay for their tickets than those passengers that pre-bought their tickets?
Reasoning: Pre - bought: 20 people * $155 = $3100. Gate bought: 30 people * $200 = $6000. $6000 - $3100 = $2900. The passengers that paid at the gate paid $2900 more dollars than those who pre - bought their tickets.

Come up with a question and reasoning that would justify [55] as the answer.
The question is: Nadine's dog rolls around in the mud. She spends 10 minutes hosing him off outside, then shampoos him three times, which takes 15 minutes per shampoo. How long does she spend cleaning her dog total?
Reasoning: First find the total shampoo time: 15 minutes / shampoo * 3 shampoos = 45 minutes. Then add the hosing off time to find the total cleaning time: 45 minutes + 10 minutes = 55 minutes.

Come up with a question and reasoning that would justify [900] as the answer.

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.
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The question is: 5,000 people live in a small town. 2,000 males live in that town and the rest of the population are females. Thirty percent of the female population wears glasses. How many females wear glasses?
Reasoning: There are 5,000 - 2,000 = 3,000 females that lives in the town. Since thirty percent of the female population wears glasses, 30 / 100 * 3,000 = 900 females wear glasses.