Irene earns $500 if she works for 40 hours a week and gets an extra $20 for every hour of overtime. If she worked 50 hours last week, calculate her total income. Let's be accurate as possible.
If Irene worked 50 hours last week, the total number of hours counting as overtime is 50 - 40 = 10 hours. Since she's given $20 for every hour of overtime, she earned 10 * $20 = $200 in overtime. Her total income, including the overtime, is $500 + $200 = $700.
The answer: 700.