MOD = 10 ** 9 + 7
N = int(input())
A = list(map(int,input().split()))
B = list(map(int,input().split()))
AB = []
for i in range(N):
    a = A[i]
    b = B[i]
    AB.append(((b-1)/a,a,b))
AB.sort(key = lambda x:-x[0])
level = 1
ans = 0
for _,a,b in AB:
    ans += level * a
    ans %= MOD
    level *= b
    level %= MOD
print(ans)