def textcost(words): #int 整体 cost = words//70 *0.1 if words%70 !=0: cost += 0.1 return cost #主程序 n = int(input()) res = 0 for x in range(n): m = int(input()) #m短消息字数量 money = textcost(m) res += money res = '{:.1f}'.format(res) print(res)