在庫 and 受注: goods in stock and an accepted production order
Separate current stock quantity from the quantity of an accepted order, without treating acceptance as finished goods already secured.
The stock currently held
在庫, read ざいこ, means stock. 青い表紙の本は在庫が一冊だけ残っていた。 reports only one copy of the blue-covered book remaining in stock.
The one-copy quantity applies to that book. It does not say that the shop had only one book of every kind combined.
Accepting an order to make or provide something
受注, read じゅちゅう, means accepting an order. 工房は学校から机十台の製作を受注した。 reports the workshop accepting a school’s order to make ten desks.
It gives the accepted production quantity without reporting ten finished desks already in warehouse stock.
Check the two quantities separately
机の在庫はありませんが、十台の製作を受注しました。 says that there are no desks in stock but an order to make ten has been accepted. An accepted order can coexist with no current stock.
在庫を数えてから、受注した数量を確認しました。 reports counting stock before checking the ordered quantity. It does not establish that the two figures matched.
Does 机十台の製作を受注した。 establish ten finished desks in stock?
Show the answer and why
No. It reports accepting an order to make ten. Completion and current stock require separate confirmation.