Find the time required for an investment of 5000 dollars to grow to 7200 dollars at an interest rate of 6.5% per year, compounded quarterly.Write an exponential equation and use logarithms to solve it.Round to 4 decimal places.Your answer is years.

解答

F in d t h e t im e re q u i re d f or an in v es t m e n t o f 5000 d o ll a rs t o g ro w t o 7200 d o ll a rs a t an in t eres t r a t e o f 6.5% p er ye a r, co m p o u n d e d q u a r t er l y . W r i t e an e x p o n e n t ia l e q u a t i o n an d u se l o g a r i t hm s t o so l v e i t . R o u n d t o 4 d ec ima l pl a ces . Y o u r an s w er i s ye a rs .

Time : 5.66

求解步骤

Translate the problem into an equation:

7200 = 5000 (1 + \frac{0.065}{4})^{4 t}

求解

t, 7200 = 5000 (1 + \frac{0.065}{4})^{4 t} : t = 5.66

Time : 5.66