42:
factor pair = 42,1
factor pair = 21,2
factor pair = 14,3
factor pair = 7,6
72:
factor pair = 72,1
factor pair = 36,2
factor pair = 24,3
factor pair = 18,4
factor pair = 12,6
factor pair = 9,8
(30,1)(15,2)(10,3)(6,5)
(42,1)(21,2)(14,3)(7,6)
1,2,3,6,7,14,21,42
(42,1)(21,2)(14,3)(7,6)
(14,1)(7,2)
42,1)(21,2)(14,3)(7,6)
42,121,214,37,6
30 has four factor pairs:30,115,210,36,5
Factor pairs of 42 are 1 x 42, 2 x 21, 3 x 14, and 6 x 7.
The factor pairs of 210 are: 1 and 210 2 and 105 3 and 70 5 and 42 6 and 35 7 and 30 10 and 21 14 and 15
The least common factor of 30 and 42 is the smallest number that is a factor of both of them and is 1.However, I suspect that you mean either:What is the highest common factor of 30 and 42?ie what is the highest number that is a factor of both 30 and 42: hcf = 6;What is the lowest common multiple of 30 and 42?ie that is the smallest number that is a multiple of both 30 and 42 lcm = 210.
(42,1)(21,2)(14,3)(7,6)
30,115,210,36,5
the only factor (divisor) between 30 and 64 are 2, this is also a factor of 42 & 196 working upwards: 1 is always a factor of integers 2 is a factor of all even numbers 3 is a factor of 30 & 42, but not 64 or 196 4 is a factor of 64 & 196, but not 30 or 42 5 is a factor of 30, but not the others 6 is a factor of 30 & 42, but not 64 or 196 7 is a factor of 42, but not the others 8 is a factor of 64, but not the others 9 is not a factor of any of the numbers 10 is a factor of 30, but not the others I could continue, but it gets worse from there, with only occasional numbers being factors...
(21,1)(7,3) (42,1)(21,2)(14,3)(7,6) Since 21 is a factor of 42, all the factors of 21 will be included in the factor pairs of 42.
The GCF of 30 and 42 is 6.
Greatest common factor of 9 30 and 42 is 3.
The GCF of 4, 30 and 42 is 2.