Question $3$ of $6$

$\frac{-}{10}*$

Skysong Boards sells a snowboard, Xpert, that is popular with snowboard enthusiasts. Information relating to Skysong's purchases of Xpert snowboards during September is shown below. During the same month, $91$ Xpert snowboards were sold. Skysong's uses a periodic inventory system.

$\backslash$table$[[$Date$,$Explanation,Units,Unit Cost,Total Cost$],[$Sept$.1,$Inventory,$21,$HK $$970,$HK $$20,370$