If the number (count) of odd values to sum is odd, then the answer is odd.
If the number (count) of odd values to sum is even, then the answer is even.
Count how many of the numbers are odd. If an odd number of them are odd, then their sum is odd. If an even number of them are odd, then their sum is even.
Even plus even equals even. Odd plus odd equals odd. Odd plus even equals odd. 13 + 45 (odd plus odd) will be even. Even plus 24 will be even. Even plus 17will be odd. 13 + 45 + 24 + 17 will be odd.
Because the sum of two odd numbers is always even and the sum of that even number plus another odd number is always odd.
The 4 is even. The 5 is odd. Their sum, 9, is odd. The sum of (one even number) + (one odd number) is always odd.
No. Sum of odd + odd = even Sum of odd + even = odd Sum of even + even = even
The sum of an odd and even number is always odd because there's always one left over. Think of any odd number as being any even number plus one. If you add two even numbers, the answer is always even. If you add an even and an odd (plus one), the answer is always odd.
The sum of an odd and even number is always odd because there's always one left over. Think of any odd number as being any even number plus one. If you add two even numbers, the answer is always even. If you add an even and an odd (plus one), the answer is always odd.
An even number can be divided by 2 evenly. An odd number will have a remainder of 1 when divided by 2. Even plus odd is odd.
The sum of an odd and even number is always odd because there's always one left over. Think of any odd number as being any even number plus one. If you add two even numbers, the answer is always even. If you add an even and an odd (plus one), the answer is always odd.
The sum of any two odd numbers is always even. This is because (a) any odd number can always be expressed as an even number plus 1, and (b) the sum of two even numbers is always even. So if X is even and Y is even then X+1 added to Y+1 will equal X+Y+2
Yes, all you have to do is to count the number of ODD numbers in the list. If it is odd, then the sum will be odd; if even, so will the sum. Knowing this can help you run a quick validity check when you sum up a list of numbers. (The method works because: a) the sum of two even numbers is even, and b) the sum pf two odd numbers is even, but c) the sum of an even number and an odd number is odd. Hence, if you only determine whether there are any unpaired odd numbers, you know the answer.)
An even number can be divided by 2 evenly. An odd number will have a remainder of 1 when divided by 2. Odd plus even is odd.