Given:
Amount after three years = $10000
Rate of interest = 8.2 percent compounded monthly = 0.082
Time = 3 years
To find:
The principal value.
Solution:
Formula for amount is
[tex]A=P\left(1+\dfrac{r}{n}\right)^{nt}[/tex]
where, P is principal, r is rate of interest, n is the number of times interest compounded in an year, t is number of years.
Substitute A=10000, r=0.082, n=12 and t=3 in the above formula.
[tex]10000=P\left(1+\dfrac{0.082}{12}\right)^{12(3)}[/tex]
[tex]10000=P\left(1+\dfrac{41}{6000}\right)^{36}[/tex]
[tex]10000=P\left(\dfrac{6041}{6000}\right)^{36}[/tex]
[tex]10000=P(1.27783)[/tex]
Divide both sides by 1.27783.
[tex]\dfrac{10000}{1.27783}=P[/tex]
[tex]7825.76712=P[/tex]
[tex]P\approx 7825.767[/tex]
Therefore, today she have to deposit $7825.767.
