n = int(input())
X = []
for _ in range(n):
    x, y = map(str, input().split())
    if not "." in x:
        X.append(int(x) * 10**10)
    else:
        x += "0" * 20
        ind = x.index(".")
        x = int(x[:ind] + x[ind+1:ind+11])
        X.append(x)

Z = []

for _ in range(n):
    x, y = map(str, input().split())
    if not "." in x:
        Z.append(int(x) * 10**10)
    else:
        x += "0" * 20
        ind = x.index(".")
        x = int(x[:ind] + x[ind+1:ind+11])
        Z.append(x)

x, z = min(X), min(Z)
print(z / x)