These numbers are all the results of multiplying 9 by an integer. For example, 9=9× 1, 18=9×2, 27=9×3, and so on until 90=9× 10. We can find that these multiples are all multiples of 10, because their single digits are all 0. At the same time, these multiples can also be divisible by 3, because the sum of their digits is a multiple of 3.
In these multiples, except 9 and 90, all the other figures are double digits. This is because 9 times any number can only be singular, and the product of two digits can only be more than two digits. Therefore, only 9 times a two-digit number can you get a multiple of a two-digit number.
Among these multiples, except 9 and 90, all others are odd numbers. This is because any odd number multiplied by 9 is odd, and even number multiplied by 9 is even. Therefore, only 9 times an odd number can you get a multiple of the odd number.
Multiplicity attribute:
1, integer multiple attribute
If one number is an integer multiple of another number, then their multiples are exactly divisible. This means that if one number is k times of another number, then this number can be divisible by k times of another number, and the result is an integer. For example, 10 is twice that of 5, so 10 can be divided by 5 twice and the result is an integer.
2. The nature of decomposition multiple
The nature of decomposition multiple means that a number can be decomposed into several identical integers to add or multiply, and this integer is the factor of this number. For example, 9 can be decomposed into 3 times 3, so 18 is the result of 3 times 3 times 2. This property can help us better understand the structure of numbers and solve some mathematical problems.
3. Unique decomposition of multiple properties
The unique decomposition multiple property means that any integer can be uniquely decomposed into the product of several prime numbers. This property can help us better understand the structure of numbers and solve some mathematical problems. For example, when solving an equation, we often need to decompose the left side of the equation into the product of several prime numbers to get the solution of the equation.