2000
its easy first multiply 200 by 1 2 3 4 and 5 than you will see 400x5=2000 So the answer is 5
Its one lap around a middle and high school track
Of course there is no way to write them all because there are an infinite number of them.Start with 400x1=400Next 400x2=800Then 400x3=1200.Keep going with 400x4, 400x5, 400x6 etc.In general the multiples of 400 are written as 400k for natural numbers k=1,2,3...