Final answer:
Maria will need to work approximately 146.34 hours at a net earning rate of $8.20 per hour after an 18% tax to pay off a $1,200 medical bill with her HSA.
Step-by-step explanation:
Maria earns $10 an hour before taxes. Given her effective tax rate of 18%, her net earnings per hour would be calculated as $10 × (1 - 0.18) = $10 × 0.82 = $8.20. Now, to cover a medical bill of $1,200 using her HSA, we need to calculate how many hours she needs to work by dividing the total bill amount by her net earnings per hour.
Hours needed = Total Bill / Net Earnings Per Hour = $1,200 / $8.20.
To find the number of hours Maria has to work to pay off the medical bill, we simply perform the division: 1200 / 8.20 ≈ 146.34 hours.
Therefore, Maria will need to work approximately 146.34 hours to earn enough money to pay her $1,200 medical bill after taxes.