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?
How much does Alfonso have to work for? ** Alfonso has to work for the $340 - $40 = $<<300=300>>300.
How much does Alfonso earn in a week? ** In a week, he earns $6 x 5 = $<<6*5=30>>30.
How many weeks does he need to work? ** Thus, he needs to work $300/$30 = <<300/30=10>>10 weeks to buy the bike.
#### 10