# -*- coding: utf-8 -*-

import sys
from collections import Counter

def input(): return sys.stdin.readline().strip()
def list2d(a, b, c): return [[c] * b for i in range(a)]
def list3d(a, b, c, d): return [[[d] * c for j in range(b)] for i in range(a)]
def list4d(a, b, c, d, e): return [[[[e] * d for j in range(c)] for j in range(b)] for i in range(a)]
def ceil(x, y=1): return int(-(-x // y))
def INT(): return int(input())
def MAP(): return map(int, input().split())
def LIST(N=None): return list(MAP()) if N is None else [INT() for i in range(N)]
def Yes(): print('Yes')
def No(): print('No')
def YES(): print('YES')
def NO(): print('NO')
# sys.setrecursionlimit(10 ** 9)
INF = 10 ** 18
MOD = 10 ** 9 + 7

N = INT()
A = LIST()
B = LIST()

def calc(t):
    A2 = [0] * N
    for i in range(N):
        A2[i] = A[i] + B[i] * t
    lsm = rsm = 0
    A2.sort()
    for i in range(N):
        lsm += A2[i] * (N-i-1)
        rsm += A2[i] * i
    res = rsm - lsm
    return res

low = 0
hi = 100
for i in range(100):
    m1 = (low*2+hi) / 3
    m2 = (low+hi*2) / 3
    res1 = calc(m1)
    res2 = calc(m2)
    if res1 <= res2:
        hi = m2
    else:
        low = m1
x = m1
print(calc(x))
