n = int(input())
scores = [int(input()) for _ in range(n)]


def calculate_score(scores: list) -> float:
    return (1 / 5) * sum([score * ((4 / 5) ** i) for i, score in enumerate(scores)])


print(calculate_score(scores))

new_scores = []
for score in scores:
    cpy_scores = scores.copy()
    cpy_scores.remove(score)
    new_scores.append(calculate_score(cpy_scores))

print(sum(new_scores) / len(new_scores))