what are all of the common factors of 105.?

Answer 1

1, 3, 5, 7, 15, 21, 35, and 105.

Answer 2

There are no "common" factors of 105. Common factros refers to factors that ar common to two different numbers. For example, 12 = 2*2*3, 14 = 2*7, teh only common facotr of 12 and 14 is 2.

You probably meant to ask what are the prime factors of 105. To get prime factors for any number begin with 2 and divide it into the number. If it goes evenly, divide it in again. When it won't go evenly, move on to 3 and etc. For example, figure the prime factors of 2940:

2940 / 2 = 1470 so 2 is a factor
1470 / 2 = 735 another factor of two
Two wont divide evenly into 735 so move to 3:
735/3 = 245 so 3 is a factor
Three wont go evenly into 735 so move to four. We can really skip four because we know that 2 wont divide so 4 sure wont. Move to 5:
245/5 = 49 so 5 is a factor
Five wont divide again. Of course 6 wont either since neither 2 or 3 will divide. Move to 7:
49 / 7 = 7
7/7 = 1
Two sevens are factors and we are done since only 1 is left. So the factors of 2940 are:

2940 = 2*2*3*5*7*7

You can do this with any whole number to determine the prime factors.

Answer 3

105 = 5 x 7 x 3, so 5, 7, and 3.

Answer 4

I may be completely mad of course but I thought that a common factor had to be a factor held in common by two numbers. 105 is only one number so where's the other number?

Answer 5

1, 3, 5, 7, 15, 21, 35, 105

Answer 6

1,3,5,7,15,21, 35 and 105

Answer 7

all factors are 1,3,5,7,15,21,35,105