There’s no solution if we got no brackets to insert. we can solve such questions only by using brackets as other contributors mentioned, “sum of 3 odd no.s can’t be even”. Sum of
3 odd numbers can’t be even.
Let k be any real number.
So, 2k+1 will be an odd number & 2k will be an even number.
Let n, m be some other random real numbers.
If we add 2k+1,2m+1,2n+1(all being odd numbers)
We get, 2k+2m+2n+3
We know that
2k,2m,2n are even numbers.
So, 2k+2m+2n is even and when you add an odd number to an even number we get an odd number.
Hence the solution is not possible.