positive numbers
Not always, if the smaller number is 0 or a negative number. Then their sum will be equal or less than the greater number.
As the need for larger numbers increased, it became necessary to use symbols to group numbers together to form larger numbers. Some examples of number representation are roman numerals as well as unary, binary and decimal code.
If you mean "the last number", there is no such thing; you can always add one more. Even infinite numbers - numbers that describe the magnitude of infinite sets - don't have a "last number"; you can always find a larger infinite number. Specifically, if you have a certain infinite number, 2 to the power of that infinite number will give you a larger infinity.
You don't always. 2 + 5 = 7, for example. But all prime numbers other than 2 are odd and two odd numbers always equal an even number when added together.
To get the range of a group of numbers you subtract the smaller number from the larger one The mean is the "average" for a group of numbers to get the mean you add all the numbers together. Then divide that number by the number in the group.
No. No matter how large of an example you choose, someone always can find a larger number (of any kind), because the upper range of number is infinite. If you take all the known prime numbers and multiply them together, then add 1 to the result, you will have a number that is not divisible by any of the known prime numbers. This number will either be prime or have prime factors that were not previously known. So, in this way, you can always find a new prime number or a number that is a multiple of new prime numbers. If the known prime numbers include all the prime numbers up to the largest known, the new ones must be larger.
Not quite.When two prime numbers of 3 and higher are added together, the result is always even, because all such prime numbers are odd numbers, and when two odd numbers are added together, the result is always an even number.However 2 is a prime number, and 2 is also an even number. Adding 2 (an even number) to a different prime number (an odd number) will always yield an odd number.Only if you don't include "2".
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The square of a number is always two numbers multiplied together. A positive times a positive is always positive, and a negative times a negative is always positive.
This does not work when one of the numbers is negative.
Generally you spell out numbers that are ten or below, between eleven and twenty you can probably do as you like. The larger a number, the less likely you are to spell it out. To be safe, you can always spell out a number and add the numeral in parentheses behind. There is no particular rule for spelling out specifically when there are multiple numbers in a sentence.