Actually, this can't be done, as shown below.
The question asks us to break up 20 into 5 odd parts, say a, b, c, d, and e.
Since a and b are odd, a+b is even.
Then since c is odd, (a+b)+c is odd.
Then since d is odd, ((a+b)+c)+d is even.
Then since e is odd, (((a+b)+c)+d)+e is odd. So this cannot be 20, which is even.
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