# Can you tell if sum of several numbers will be even or odd?

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.)

### Can you tell if the product of several numbers will be even or odd?

Yes it is possible to determine if a product will be even or odd. To do this, we need to consider what an even number is. Even numbers are numbers with at least one factor of 2 (meaning they are divisible by 2). Thus, any product of numbers which contains at least one even number will result in an even product. If all of the numbers being multiplied together are odd, the product will be…

### Can 5 odd numbers that if you add them make 32?

No. The sum of two odd numbers or two even numbers is an even number. The sum of an even number and an odd number is an odd number. The sum of 5 odd numbers is: ((odd + odd) + (odd + odd)) + odd = (even + even) + odd = even + odd = odd But 32 is an even number, therefore it cannot be the sum of 5 odd numbers.

### When multiplying an odd number by an odd number why is the result odd?

The product of multiplication results in a number that has all of the factors of the two numbers being multiplied. All even numbers have the prime factor 2. Since no odd number has the factor 2, no product of those numbers can have it. So: - Odd numbers times odd numbers produce odd numbers. - Odd numbers times even numbers produce even numbers. - Even numbers times even numbers produce even numbers.

### How can you determine whether the sum of several numbers such as 13 45 24 17 is even or odd without actually calculating the sum?

Just add the end numbers, so 3 + 5 + 4 + 7 = 19 which is odd. Alternatively, ignore even numbers [such as 4], and two odd numbers [3 and 5] added always make an even number [8], which leaves and odd number [7] so the answer will be odd. Example; five hundred different numbers, where 483 are even and 17 are odd, then no matter what the actual 500 numbers are the answer…

### How could you determine whether a sum of numbers such as 127 plus 38 is even or odd?

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…

### What five odd numbers add up to 100?

No 5 odd numbers add up to 100. The sum of any two odd numbers is even. The sum of any two even numbers is even. So the sum of any 4 odd numbers must be even. Take that and add an odd number and the sum must be odd. Therefore, the sum of any 5 odd numbers must be odd. 100 is even. In conclusion: The sum of any odd number of odd numbers…

### What 7 odd numbers that will total 30?

You cannot do this, because you're taking odd numbers: if you add two odd numbers together, you will get an even number. Take the odd numbers in pairs, so you'll have 3 pairs plus an extra odd number. The 3 pairs make 3 even numbers. You can add up any number of even numbers and get an even number, so you will have an even + odd, which is odd. 30 is an even number…

### What 5 odd numbers equal 30 when added and you can use the odd numbers more than once?

There are no 5 odd numbers that when added together make 30. Two odd numbers added together make an even number An odd number plus and even number makes an odd number. From the five odd numbers: Take two of them and add them together getting an even number and four odd numbers Add another of the odd numbers to this even number and you will have three odd numbers Add two of these together…

### 9999555533331111 in these any six numbers total is 21 what are those numbers?

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…

### Is the GCF of any two numbers always odd and why?

The GCF of any two odd numbers is always odd because odd numbers don't have any even factors. The GCF of any two even numbers is always even because even numbers are divisible by two and any common factors would have at least one two in common. The GCF of an even and an odd number is odd because odd numbers don't have any even factors.