They can be 18 and 27
9 and 18
6 and 9
Pick any two coprime numbers. Multiply both by 9. Their GCF will be 9.
The pair of numbers whose GCF is 1 and LCM is 36 is 9 and 4. The numbers should be greater than their GCF and less than their LCM.
A number can't have a factor greater than itself, so the GCF of a pair of numbers can't ever be greater than the smaller number. The GCF of 9 and 18 is 9.
To find a pair of numbers with a given GCF, take the GCF number and double it. The pair of numbers is the GCF, and two times the GCF. For instance, two numbers with a GCF of 3 are 3 and 6.
4 and 9
6 and 9, among many others.
1 and 36 4 and 9
3 and 36 9 and 12
9 and 12
The GCF is a single number so there cannot be any pair of numbers in the answer.