Answer
$\$ 143.12$
Work Step by Step
A sinking fund is an account earning compound interest into which you make periodic deposits. $\\$
$FV=PMT\displaystyle \cdot\frac{(1+i)^{n}-1}{i}, \quad PMT=FV\cdot\frac{i}{(1+i)^{n}-1}$
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given: $\\$
$FV=20,000$
$t=10$ years,
annual rate: r =$0.03$
m= $12 \ \ \ $compounding periods per year,
$\displaystyle \mathrm{i}=\frac{r}{m}=\frac{0.03}{12}=$0.0025 $\ \ $(rate per compounding period$)$
$n=mt=120 \ \ $(total number of periods)
$PMT=?\ \ \ $( payment at the end of each period)
$PMT=FV\displaystyle \cdot\frac{i}{(1+i)^{n}-1}$
$=20,000\displaystyle \cdot\frac{0.0025}{(1+0.0025)^{120}-1}$
$\approx$143.121489397
