n = io.read("*n")
t = {}
sum = 0
for i = 1, n do
    a = io.read("*n")
    t[i] = a
    sum = sum + a
end
cnt = 0
for i = 1, n do
    if(t[i] * 10 <= sum) then cnt = cnt + 1 end
end
print(cnt * 30)