why is it that everything you do to nine, the numbers in the answer add up to nine? e.g 5 x 9 = 45, 4 + 5 =9?

Answer 1

Your statement is not true. It is true that for the product of 9 and any positive integer, the sum of its digits is a multiple of 9. See the reference for this and other interesting properties of 9. No one here has yet answered this. A key is the fact that our number system is base 10.

Answer 2

Following the rules of your wording, it doesn't always add up to 9. e.g. 9/9=1, 9+17=26 then 2+6=8. However when you multiply 9 by any whole number and add the numbers in the answer, it appears to me that you do always end up with nine. That is a sure indicator to young students when learning division that if the digits in the number add up to nine, the number can be divided by nine. A similar rule applies to the number three. If three can go into the last digit of a number, then that number is divisible by 3.

Answer 3

9 will divide any number where the sum of the digits is divisible by 9. For example you can find out that 9 divides 3873213 just by adding each number 3+8+7+3+2+1+3=27. This is because numbers 10 to power n (for any n) always leave a remainder of 1 when divided by 9. I remember this from a symbolic computation course I took.

Answer 4

It's not true. For instance

11 x 9 = 99
9+9 does not equal 9

55 x 9 = 495
4+9+5 does not equal 9

Answer 5

The answer is have you done the trick of nines ..
v (follow down)
1x9= 09
2x9= 18
27
36
45
54
63
72
81
90
^ (follow up)

Answer 6

Our value system is based on 10 as the base. In numerology the actual value numbers are 1 to 8 only. 9 actually does not contribute to any value and so its value by itself is 9, but numerologically it contributes to 0, or its own value of 9. The number given to Jesus is 888. For satan it is 666, while to YAHWEH it is 444. For man it is 6.

Answer 7

One of life's little mysteries but isn't it great?

Answer 8

i dont know its one of those rules in math

Answer 9

its a rule in maths.