It is called the digital sum. If you keep doing it until you reach a single digit answer, it is called a digital root. The term digital root is sometimes also used for the digital sum.
For example,
3042 gives the digital sum of 3+0+4+2 = 9 which is also its digital root.
but
3047 gives the digital sum of 3+0+4+7 = 14 and the digital root is 1+4 = 5.
They are called the digital roots.
The different digits have different values.
Individual digits within a number have place values, not whole numbers.
A single digit in a number can have a place value. A number with several digits cannot.
If it's a one-digit number then any 1-digit number will do (0...9) 2-digits numbers : ab=10a+b=a+b it's not possible unless a=0 For 3-digits: abc=100a+10b+c=a+b+c => 100a+10b = a+b it' not possible unless a=b=0 And so on...
The correct answer is "expanded form".
They are called the digital roots.
The different digits have different values.
Individual digits within a number have place values, not whole numbers.
Any even number.
A single digit in a number can have a place value. A number with several digits cannot.
to show the cardinal and face values
If it's a one-digit number then any 1-digit number will do (0...9) 2-digits numbers : ab=10a+b=a+b it's not possible unless a=0 For 3-digits: abc=100a+10b+c=a+b+c => 100a+10b = a+b it' not possible unless a=b=0 And so on...
Zero or five.
Mutilply the values of the digits.
They make the numbers invisible to the people at Answers.com, possibly.
The one's digit can only be 5 or 0.