prompt: Matilda bought a smartphone for $300. Then she decided she wouldn't use it anyway and sold it for $255. What percentage of the initial cost did she lose?
messages.content: Matilda bought a smartphone for $300. Then she decided she wouldn't use it anyway and sold it for $255. What percentage of the initial cost did she lose?
messages.role: user
messages.content: The difference between the initial cost and the amount she sold the phone for is $300-$255 = $<<300-255=45>>45
  $45 is (($45/$300)*100)% = 15% of $300
  #### 15
messages.role: assistant