Jasmine, uses 2 gallons of paint to pay five walls. He uses 4 gallons of paint to take to paint 10 walls. How many gallons of paint does she use per wall?

To paint 5 walls, Jasmine uses 2 gallons of paint so she uses 2/5 = <<2/5=0.4>>0.4 gallons of paint per wall.

To paint 10 walls, Jasmine uses 4 gallons of paint so she uses 4/10 = <<4/10=0.4>>0.4 gallons of paint per wall. Answer: \boxed{0.4}.