Alfonso earns $6 each day walking his aunt’s dog. He is saving to buy a mountain bike helmet for $340. Currently, he already has $40. If he walks his aunt's dog 5 days a week, in how many weeks should Alfonso work to buy his mountain bike?
Alfonso has to work for the $340 - $40 = $<<300=300>>300.
In a week, he earns $6 x 5 = $<<6*5=30>>30.
Thus, he needs to work $300/$30 = <<300/30=10>>10 weeks to buy the bike.
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