n,k=map(int,input().split(" "))

l1=[]

l2=[]

for i in range(2,n):

if i%k==0:

    l1.append(i)

else:

	l2.append(i)

m=0

t=0

for l in l1:

m=m+l

for l in l2:

t=t+l

q=m/len(l1)

p=t/len(l2)

print(f"{float(q):.1f} {float(p):.1f}")