N = int(input())
A = list(map(int,input().split()))
B = list(map(int,input().split()))
mod = 10**9+7

C = []

for i,v in enumerate(A):
    tmp = (B[i]-1)/A[i]
    C.append([tmp,i])

C.sort()
C.reverse()

level = 1
ans = 0

for i,v in enumerate(C):
    tmp1 = v[1]
    ans+=level*A[tmp1]
    ans%mod
    level*=B[tmp1]
    level=level%mod

print(ans%mod)