import sys
input = sys.stdin.readline

N = int(input())
for _ in range(N):
    T, m, L = map(float, input().split())
    lb, ub = 0, 10**7
    while ub - lb > 1:
        v = (lb + ub) // 2
        if 20*m*360*T*v + v**2 <= 20*m*360**2*L:
            lb = v
        else:
            ub = v
    ans = str(lb)
    while len(ans) < 3:
        ans += "0"
    ans = ans[:-2] + "." + ans[-2:]
    print(ans)