The GCF is 7.
The GCF is 7.
There can only be one "highest".Here's how to find it:Factors of 35: 1, 5, 7, and 35Factors of 45: 1, 3, 5, 9, 15, and 45Common factors: 1 and 5Highest common factor ===> 5
20 and 40 have 4 and 5 as common factors.
27 and 28 have no common factors other than one. Any pair of consecutive integers is coprime, and such a pair's only common factor is 1.
The common factor is 1.
1 and 2
12 and 24
12 and 24
21 and 42
All numbers have common multiples.
Yes, a pair of numbers can have fewer than two common factors. This only happens when the numbers are co-prime -- that is, when the numbers have only one common factor. In that case, the common factor is always 1.
It is common to group factors in pairs with parentheses surrounding each pair.