Three whole numbers add up to 50 all three numbers.All three numbers must be even. Is it correct?

Incorrect.

 

you can have two odds + even     OR   three  evens        (you cannot have three odds or two evens + odd)

   example:   21   21  8                              18 12  20 

 

Three whole numbers add up to 50 all three numbers.All three numbers must be even. Is it correct?     

 

MUST be?  All you need is one exception to disprove this. 

 

Here's one:  1, 1, 48   So the answer is No, that is not correct. 

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