90 and 180 have a GCF of 90.
40 and 50
The GCF is 2.
The GCF is 2.
That cannot be determined. The GCF of 1, 2 and 87 is 1. The GCF of 15, 30 and 45 is 15. The GCF of 90, 180 and 270 is 90 on the chance that that is what you meant to ask.
40 and 50
You need at least two numbers for a GCF.
The GCF is 10.
The GCF of any two numbers can only be one number: it cannot be 30 as well as 90.
The GCF of 90 and 180 is 90.
45 and 10