Yes! 40:70 can be simplified! A ratio can be simplified if both numbers have a GCF that is not 1. Looking at 40 and 70, we see that they have a GCF of 10. That means that to simplify 40:70, we need to divide both numbers by 10. 40/10 = 4, and 70/10 = 7, so that means that our simplified ratio is 4:7.