The stock worth when she sells it eight years later $545, If the stock decreases at a rate of 15% per year for eight years.
According to the question,
Petra opens her mail one day to find that an anonymous donor has given her $3000 cash. She sets aside $1000 to refurnish her apartment, and decides to invest the other $2000.
If the stock decreases at a rate of 15% per year for eight years. In order to find the stock worth when she sells it eight years later we have the formula
Value of stock after 'n' years = Principal[1-Rate/100]ⁿ
Value of stock after '8' years = 2000[1-15/100]⁸
= 2000[1-0.15]⁸
=2000[0.85]⁸
=2000[0.2725]
=545$
Hence, the stock worth when she sells it eight years later $545, If the stock decreases at a rate of 15% per year for eight years.
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