If the estimated rate of gross profit is $30\%,$ what is the estimated cost of the inventory on September $30,$ based on the following data

Sep. $1$ Inventory $($at cost$)$

Sep. $1-30$ Purchases, net $($at cost$)$

Sep. $1-30$ Sales

$$85,768$

$198,000$

$127,400$

a$.$ $$38\mathrm{.}220$

b$.$ $$194,588$

c$.$ $$89,180$

d$.$ $$59,400$