What numbers can be used to fill the blanks?
Fill the blanks with the valid numbers.
If we don't have any brackets to insert, there is no solution. As previous contributors pointed out, we can only solve such issues by using brackets, as in 'the total of three odd numbers can't be even.' It's impossible for the sum of three odd numbers to be even.
Proof:
Any real number can be substituted for .
So, is an odd number and is an even number.
Let be any other arbitrary real number.
Now, add (all being odd numbers)
We get,
We know that
are even numbers.
So, is even, and we obtain an odd number when we add an odd number to an even number.
Therefore, the solution is not possible.