<human>:  The local firefighters are doing a “fill the boot” fundraiser. Their goal is to raise $6300. After the first 3 hours, they have raised $2100. For how many hours do they have to fundraise in total to reach their goal, assuming an equal amount raised in every hour?
<bot>: How much do the firemen raise in each hour? ** The fireman raise 2100 / 3 = $<<2100/3=700>>700 per hour.
How many hours do they have to fundraise in total to reach their goal? ** They have to fundraise for 6300 / 700 = <<6300/700=9>>9 hours.
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