5 and 10
You can reduce the number by known factors to make it more manageable. Plus there are tricks for different numbers: If the number is even, then 2 is a factor. If the digits add up to a multiple of 3 then 3 is a factor. If the ones digit is a 5 or 0 (with a tens digit greater than or equal to 1), then 5 is a factor. If the ones digit is a 0 then 10 is a factor. If the digits have the property that the first minus the second, plus the third, minus the fourth, (alternating signs) equals 0, then 11 is a factor. There are other tricks but these factors would be the most common.
Numbers that end in zero are multiples of 10 and must have 1, 2, 5 and 10 as factors.
Every six-digit number is greater than any five-digit number.
16
If the result has a remainder of 6, then the number must be 165 + 6. So you need to find all the 2-digit factors of 165. The easiest way is to just start listing them and see what you get. Start with 10, then go to 11, etc and write the factor pairs. If some number is not a factor of 165, just skip it and go to the next number. When the factors start to repeat, you are done. The two-digit factors of 165 10 × ___ <-- 10 is not a factor, so skip it and go to the next number 11 × 15 12 × ___ <-- Not a factor. Skip to the next number 13 × ___ <-- Not a factor 14 × ___ <-- Skip this one 15 × 11 <-- The factors are repeating, so you are done. Answer: The only two-digit numbers that divide 171 with a remainder of 6 are 11 and 15 Check 171 ÷ 11 = 15 R6 171 ÷ 15 = 11 R6 Check!
1, 2, 5 and 10
It must be a multiple of ten, so it must have the factors 1, 2, 5 and 10.
The two-digit factors of 100 and 1000 are all composite.
You can reduce the number by known factors to make it more manageable. Plus there are tricks for different numbers: If the number is even, then 2 is a factor. If the digits add up to a multiple of 3 then 3 is a factor. If the ones digit is a 5 or 0 (with a tens digit greater than or equal to 1), then 5 is a factor. If the ones digit is a 0 then 10 is a factor. If the digits have the property that the first minus the second, plus the third, minus the fourth, (alternating signs) equals 0, then 11 is a factor. There are other tricks but these factors would be the most common.
Both 10 and 20 are two-digit numbers that are factors of 20.
Sure. Any 1-digit number contains only one-digit numbers as factors. Any larger number, on the other hand, contains itself as a factor, so these can be excluded.
i do not really know because i am the one that asked the quetion.
720.
Every six-digit number is greater than any five-digit number.
2 is a prime number and has no factors other than 1 and itself.
There is no single digit number greater than 9. After 9 is 10, which is a double-digit number.
Numbers that end in zero are multiples of 10 and must have 1, 2, 5 and 10 as factors.