Answer:
t≈ 8
Explanation:
\text{Compounded Monthly:}
Compounded Monthly:
A=P\left(1+\frac{r}{n}\right)^{nt}
A=P(1+
n
r
)
nt
Compound interest formula
A=109700\hspace{35px}P=97000\hspace{35px}r=0.016\hspace{35px}n=12
A=109700P=97000r=0.016n=12
Given values
109700=
109700=
\,\,97000\left(1+\frac{0.016}{12}\right)^{12t}
97000(1+
12
0.016
)
12t
Plug in values
109700=
109700=
\,\,97000(1.0013333)^{12t}
97000(1.0013333)
12t
Simplify
\frac{109700}{97000}=
97000
109700
=
\,\,\frac{97000(1.0013333)^{12t}}{97000}
97000
97000(1.0013333)
12t
Divide by 97000
1.1309278=
1.1309278=
\,\,1.0013333^{12t}
1.0013333
12t
\log\left(1.1309278\right)=
log(1.1309278)=
\,\,\log\left(1.0013333^{\color{blue}{12t}}\right)
log(1.0013333
12t
)
Take the log of both sides
\log\left(1.1309278\right)=
log(1.1309278)=
\,\,\color{blue}{12t}\log\left(1.0013333\right)
12tlog(1.0013333)
Bring exponent to the front
\frac{\log\left(1.1309278\right)}{\log\left(1.0013333\right)}=
log(1.0013333)
log(1.1309278)
=
\,\,\frac{12t\log\left(1.0013333\right)}{\log\left(1.0013333\right)}
log(1.0013333)
12tlog(1.0013333)
Divide both sides by log(1.0013333)
92.3402971=
92.3402971=
\,\,12t
12t
Use calculator
\frac{92.3402971}{12}=
12
92.3402971
=
\,\,\frac{12t}{12}
12
12t
Divide by 12
7.6950248=
7.6950248=
\,\,t
t