mod = 10**9+7
N = int(input())
A = list(map(int,input().split()))
B = list(map(int,input().split()))
C = []
for i in range(N):
    C.append(((B[i]-1)/A[i], i))
C.sort(reverse=True)
ans = 0
x = 1
for i in range(N):
    idx = C[i][1]
    ans += A[idx] * x
    x *= B[idx]
    ans %= mod
    x %= mod
print(ans)