Answer:
a. almost 8 years
Explanation:
Brenda's expected annual increase in salary is ...
$63,292 -45,258 = $18,034
If we assume that Brenda's cost of education includes going without 2 years' salary as well as the cost of tuition, her degree's total cost will be ...
2×$45,258 +15,000 = $105,516
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Once Brenda starts earning again, she is recovering this cost at the rate of $18,034 per year, so it will take ...
$105,516/($18,034 /yr) = 5.85 yr
to recover that cost.
Since Brenda spent 2 years in school, from the time she decides to start school until she has recovered her cost, it will be 2 + 5.85 = 7.85 years, almost 8 years.
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If Brenda can continue working while going to school, she can recover her tuition cost in about 10 months after graduation.