The PROPER factor of 19 is 1 and just 1. Since 19 is a prime number its only proper factor is 1. Any prime number only has 1 proper factor which is 1.
No.
No.
4 3 and 6 have no proper factor in common. Remember that 1 is a factor of every counting number, but not a proper factor of any of them. Greatest common factor questions do not recognise 1 as a proper factor. When talking of primes neither 1 nor the number itself is regarded as a proper factor.
a proper factor is a factor.
The proper factor of 21 is 1, 3 and 7
The proper factors of 99 are: 1, 3, 9, 11, 33. A proper factor is any factor of the number that is not itself.
Traditionally no.
The factors of 9 are 1, 3 and 9. The proper factor of 9 is 3.
No, 294 is not a proper factor of 147. Proper factors are smaller than the number of which they are a factor. The proper factors of 147 are 3, 7, 21, 49, and perhaps 1, depending on the definition you are using.
The only common factor is 1. There is no proper common factor.
No. Prime numbers don't have proper factors.