



 
Hi Delores, First I needed to know how many cubic feet are in 3000 gallons, so I asked Google. I typed 3000 gallons in cubic feet into Google's search window and got the response 3000 US gallons = 401.041667 cubic feet. Hence if your length is $L$ feet then $8 \times 6 \times L = 401.04$ thus \[L = \frac{401.04}{8 \times 6} = 8.4 \mbox{ feet.}\] Penny  


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