human
Mitch has saved $20000 to finance his boating hobby. A new boat costs $1500 per foot in length. If Mitch needs to keep $500 for a license and registration, and three times that amount for docking fees, how many feet is the longest boat he can buy?
assistant
How much money does Mitch need to keep for docking fees? ** Mitch needs to keep 500 * 3 = <<500*3=1500>>1500 for docking fees.
How much money does Mitch need to keep? ** Thus, he needs to keep 500 + 3 * 500 = $<<500+3*500=2000>>2000 for license, registration, and docking fees.
How much money does Mitch have left to spend? ** He has 20000 - 2000 = $<<20000-2000=18000>>18000 left to spend on a boat.
How many feet is the longest boat he can buy? ** Therefore, the longest boat he can buy is 18000 / 1500 = <<18000/1500=12>>12 feet long.
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