The slightly old-fashioned expression DUCK SOUP means sth that is very easy to do:
The expedition was duck soup for him. It only took him three days.
This math problem was supposed to be duck soup, but I’m still trying to sort it out.
So, my job is to carry the box to the other side of the room? It’s duck soup!
He’s an expert, so this problem is going to be duck soup for him.
It’s duck soup. Just press the button and it will work.
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