The GCF is 70.
840 and 70, respectively.
Find a number in that range that you know is a multiple of 7, like 210 or 280. Add 7 to it. 210 and 217 have a GCF of 7. 280 and 286 have a GCF of 7.
210 and 420 have a GCF of 210.
Since 210 is a factor of 420, it is automatically the GCF.
The GCF is 4.
The GCF is 70.
The GCF is 40.
The GCF of 531 and 280 is 1.
There is a 25% decrease in 280 to 210. 25% = 70
The GCF is 42.
The GCF is 105.
The GCF is 1.