The input contains between 1 and 10 lines, *i*-th line contains an integer number *x*<sub class="lower-index">*i*</sub> (0 ≤ *x*<sub class="lower-index">*i*</sub> ≤ 9).
foo = 0
bar = 0
baz = 0
quz = 0
for _ in range(int(input()):
    pur = int(input())
    foo += pur
    bar += 1
    if(foo*quz>=bar*baz):
        baz = foo
        quz = bar
    else:
        break
print(baz/quz)
    