from fractions import Fraction
MOD = 10**9+7
N = int(input())
A = list(map(int,input().split()))
B = list(map(int,input().split()))

a = []
for i in range(N):
    if(A[i] == 0):continue
    a.append((Fraction(B[i],A[i]),A[i]))
a.sort()

now = 0
for v,num in a:
    now += num
    if(now >= -(-N//2)):
        b,c = v.as_integer_ratio()
        print(b * pow(c,-1,MOD) % MOD)
        exit()