from operator import le


n = int(input())
A = list(map(int,input().split()))
B = list(map(int,input().split()))
mod = 10**9+7
X = []
for a,b in zip(A,B):
    c = (b-1)/a
    X.append([c,a,b])
X.sort(reverse=True)
ans = 0
level = 1
for x,a,b in X:
    ans += a*level
    ans %= mod
    level *= b
    level %= mod
print(ans)