Answer:
$288,000
Explanation:
The reason is that $42000 is 60% percent value at the end of the year.
So to find the opening balance of work in progress which is 100% in value we will simply divide this $42,000 by 60%.
Opening Work In Process = $42,000 / 60% = $70,000
And now,
The cost of goods manufactured = Opening Work In Process + Manufacturing cost for the period - Closing Work In Process
The cost of goods manufactured = $70,000 + $260,000 - $42,000
= $288,000