conversations.from: human
conversations.value: This math problem has got me stumped: Nancy's ex owes her child support. He's supposed to pay 30% of his income each year. For 3 years, he made $30,000/year, then he got a 20% raise for the next four years. If he's only ever paid $1,200, how much does he owe her?
  Can you show me the way?
conversations.from: assistant
conversations.value: First find how much money the ex made during the first 3 years by multiplying his annual earnings by the number of years: 3 years * $30,000/year = $90,000/
  Then find how much his raise was by multiplying his salary by the percentage raise: $30,000/year * 20% = $6,000/year
  Then add the raise to his original salary to find his new salary: $6,000/year + $30,000/year = $36,000/year
  Then find how much he made working at the new salary by multiplying it by the 4 years he worked: 4 years * $36,000/year = $144,000
  Add his earnings from the three years and the four years to find his total earnings: $144,000 + $90,000 = $234,000
  Now multiply his total earnings by 30% to find how much he was supposed to pay: $234,000 * 30% = $70,200
  Now subtract the amount he paid from this number to find how much he owes: $70,200 - $1,200 = $69,000