0: 99,959
1: 99,757
2: 100,026
3: 100,230
4: 100,230
5: 100,359
6: 99,548
7: 99,800
8: 99,985
9: 100,106
28
Add the digits together. The sum of the digits of 23 is 5.
It has five digits each of them representing numerical quantities
None.
A delectable number has nine digits, using the numbers 1-9 once in each digit. The first digit of a delectable number must be divisible by one. The first and second digits must be divisible by two, the first through third must be divisible by three, etc. There has only been one delectable number discovered: 381654729.
3.14159265
10 digits to select for the first number in the sequence 10 digits to select for the second number in the sequence for each possible option of 10 digits in the first slot in the sequence (10 * 10) 10 digits to select for the third number in the sequence for each possible option of 10 digits in the second slot for each possible digit in the first slot of the sequence (or more easily put, 10 possible digits for each of 100 potential first two number sequences) [10*10*10] etc.... =10 * 10 * 10 * 10 * 10 * 10 * 10 = 10^7 = 10,000,000 (10 Million) Now add an area code before that 7 digit phone number and you get 10 Billion combinations (of course there are exclusions such as any sequence starting in 911 would be prohibited which is a reduction of 10 million numbers itself - 911 000 0001, 911 000 0002, etc. There are many other exclusions as well such as can't start with 0 - this removes another 1 billion sequences)
28
1
Add the digits together. The sum of the digits of 23 is 5.
About 100,000 of each.
There is a choice of 8 digits for the first digit and a choice of 10 digits for each of the remaining 6, so there are 8 x 106 = 8,000,000 (eight million) 7-digit numbers which do not start with 0 or 4.
It has five digits each of them representing numerical quantities
Assuming that 2356 is a different number to 2365, then: 1st digit can be one of four digits (2356) For each of these 4 first digits, there are 3 of those digits, plus the zero, meaning 4 possible digits for the 2nd digit For each of those first two digits, there is a choice of 3 digits for the 3rd digit For each of those first 3 digits, there is a choice of 2 digits for the 4tj digit. Thus there are 4 x 4 x 3 x 2 = 96 different possible 4 digit numbers that do not stat with 0 FM the digits 02356.
None.
by moving each digits
By the sum of its digits: 10. By each of its individual digits: 11.