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?
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 = $
<gadget id="calculator">3*30000</gadget>
<output>90_000</output>
90,000/
Then find how much his raise was by multiplying his salary by the percentage raise: $30,000/year * 20% = $
<gadget id="calculator">30000*20*.01</gadget>
<output>6_000</output>
6,000/year.
Then add the raise to his original salary to find his new salary: $6,000/year + $30,000/year = $
<gadget id="calculator">6000+30000</gadget>
<output>36_000</output>
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 = $
<gadget id="calculator">4*36000</gadget>
<output>144_000</output>
144,000.
Add his earnings from the three years and the four years to find his total earnings: $144,000 + $90,000 = $
<gadget id="calculator">144000+90000</gadget>
<output>234_000</output>
234,000.
Now multiply his total earnings by 30% to find how much he was supposed to pay: $234,000 * 30% = $
<gadget id="calculator">234000*30*.01</gadget>
<output>70_200</output>
70,200.
Now subtract the amount he paid from this number to find how much he owes: $70,200 - $1,200 = $
<gadget id="calculator">70200-1200</gadget>
<output>69_000</output>
69,000.

<result>69_000</result>