23-13
= 10
Multiply two odd numbers Add an even and an odd Subtract an odd and an even
Any two odd numbers will have an odd product and an even sum.
Any pair of one even and one odd number will have an even product and an odd sum.
The parity rules are: Odd + Odd = Even Even + Even = Even Odd + Even = Odd Even + Odd = Odd So the parity where one number is even is that of the other number. This means that you can go through a list of numbers and ignore all the even numbers. Every PAIR of odd numbers has even parity and by the previous paragraph, even parity can be ignored. So you can pair off odd numbers and ignore them.
yes
If you add, subtract, or multiply two even numbers, you will get an even number. If you divide an even number by another even number, you may get an even number, an odd number, or even a fraction.
5+5+5+5+1 That is only 5 numbers being added. There can be no answer for six numbers for the following reasons: The numbers are all odd. Two odd numbers make an even number. Two even numbers make an even number. 21 is odd. Take 6 odd numbers and add them up in pairs. Each pair of odd numbers gives an even number so there are 3 even numbers. Even + Even + Even = Even. So sum of any six odd numbers is even but 21 is not even.
They have the same parity (odd or even).
Odd. First subtract 1 less than your odd number, (which is obviously even) to get even - even, which is even. Then take off your spare 1 to finish up odd.
you get an odd number
37
There is no such pattern because there are no even odd numbers. Odd numbers, by definition, are odd and therefore, not even.