conversations.from: human
conversations.value: Can you explain how to solve this math problem: Penny has $20. Penny buys 4 pairs of socks for $2 a pair and a hat for $7. How much money does Penny have left?
conversations.from: assistant
conversations.value: Penny buys 4 pairs of socks for $2 x 4 = $8.
  In total, Penny spent $8 + $7 = $15 on 4 pairs of socks and a hat.
  Penny has $20 -$15 = $5 left after buying 4 pairs of socks and a hat.