999 are whole.
for digits 0 to 9 0,1,3,8 have lines of symmtery
All whole numbers are divisible by 1. Numbers are divisible by 2 if they end in 2, 4, 6, 8 or 0. Numbers are divisible by 3 if the sum of their digits is divisible by 3. Numbers are divisible by 4 if the last two digits of the number are divisible by 4. Numbers are divisible by 5 if the last digit of the number is either 5 or 0. Numbers are divisible by 6 if they are divisible by 2 and 3. Numbers are divisible by 9 if the sum of their digits is equal to 9 or a multiple of 9. Numbers are divisible by 10 if the last digit of the number is 0.
There are 9 digits that can be the first digit (1-9); for each of these there is 1 digit that can be the second digit (6); for each of these there are 10 digits that can be the third digit (0-9); for each of these there are 10 digits that can be the fourth digit (0-9). → number of numbers is 9 × 1 × 10 × 10 = 900 such numbers.
∞ \ Infinite
999 are whole.
Digits
for digits 0 to 9 0,1,3,8 have lines of symmtery
All whole numbers are divisible by 1. Numbers are divisible by 2 if they end in 2, 4, 6, 8 or 0. Numbers are divisible by 3 if the sum of their digits is divisible by 3. Numbers are divisible by 4 if the last two digits of the number are divisible by 4. Numbers are divisible by 5 if the last digit of the number is either 5 or 0. Numbers are divisible by 6 if they are divisible by 2 and 3. Numbers are divisible by 9 if the sum of their digits is equal to 9 or a multiple of 9. Numbers are divisible by 10 if the last digit of the number is 0.
I assume you mean the sum of the digits.If the first digit is 1, the other two digits have to sum 10. There are 9 different possibilities for this, from 1 + 9 to 9 + 1.If the first digit is 2, the other two digits have to sum 9. There are 10 different possibilities for this, 0 + 9 to 9 + 0.Adding it all up, it seems there are 19 such numbers.
There are 9 digits that can be the first digit (1-9); for each of these there is 1 digit that can be the second digit (6); for each of these there are 10 digits that can be the third digit (0-9); for each of these there are 10 digits that can be the fourth digit (0-9). → number of numbers is 9 × 1 × 10 × 10 = 900 such numbers.
∞ \ Infinite
The natural numbers, in normal usage, have only 9 digits: 0, 1, 2, 3, 4, 5, 6, 7, 8 and 9.The natural numbers, in normal usage, have only 9 digits: 0, 1, 2, 3, 4, 5, 6, 7, 8 and 9.The natural numbers, in normal usage, have only 9 digits: 0, 1, 2, 3, 4, 5, 6, 7, 8 and 9.The natural numbers, in normal usage, have only 9 digits: 0, 1, 2, 3, 4, 5, 6, 7, 8 and 9.
There are 9 possible numbers for the first digit (one of {1, 2, ..., 9}); with 9 possible digits for the second digit (one of {0, 1, 2, ..., 9} which is not the first digit)); with 8 possible digits for the third digit (one of {0, 1, 2, ..., 9} less the 2 digits already chosen); This there are 9 × 9 × 8 = 648 such numbers.
There are none.Any number made by using the digits 0 to 9 once is divisible by 9 and so not a prime.There are none.Any number made by using the digits 0 to 9 once is divisible by 9 and so not a prime.There are none.Any number made by using the digits 0 to 9 once is divisible by 9 and so not a prime.There are none.Any number made by using the digits 0 to 9 once is divisible by 9 and so not a prime.
9
Yes. Whole Numbers are the numbers 0, 1, 2, 3, . . . . I remember whole numbers by thinking of the O in "whole" -- whOle.