sr=input().split()
x1=int(sr[0])
x2=int(sr[1])
n=int(sr[2])
zhensu=x1//x2
s=str(zhensu)+"."
yushu=x1%x2
for i in range(n):
    div1=yushu*10
    s=s+str(div1//x2)
    yushu=div1%x2
print(s)
/**************************************************************
	Problem: 1271
	User: admin
	Language: Python
	Result: Accepted
	Time:95 ms
	Memory:34480 kb
****************************************************************/