above average acm大赛题目。有待改进。-Descr iption



It is said that 90　of frosh expect to be above average in their class. You are to provide a reality check.



Input



The first line of standard input contains an integer C, the number of test cases. C data sets follow. Each data set begins with an integer, N, the number of people in the class (1 <= N <= 1000). N integers follow, separated by spaces or newlines, each giving the final grade (an integer between 0 and 100) of a student in the class.



Output



For each case you are to output a line giving the percentage of students whose grade is above average, rounded to 3 decimal places.



Sample Input



5

5 50 50 70 80 100

7 100 95 90 80 70 60 50

3 70 90 80

3 70 90 81

9 100 99 98 97 96 95 94 93 91



Sample Output





40.000

57.143

33.333

66.667

55.556