#include <stdio.h>
#include <string.h>

int main()
{
	struct person
	{
		char firstname[30];
		char lastname[30];
		int math;
		int inf;
		int rus;
		float sr;
	};

	int N;
	scanf("%d", &N);
	struct person info[N];

	float balls = 0.0;
	for (int i = 0; i < N; i++)
	{
		scanf("%s", info[i].firstname);
		scanf("%s", info[i].lastname);
		scanf("%d", &info[i].math);
		scanf("%d", &info[i].inf);
		scanf("%d", &info[i].rus);
		info[i].sr = (info[i].math + info[i].inf + info[i].rus) / 3;
		balls += info[i].math + info[i].inf + info[i].rus;
	}

	balls /= N*3;
	printf("%f\n", balls);

	for (int i = 0; i < N; i++)
	{
		if (info[i].sr > balls)
			printf("%s %s\n", info[i].firstname, info[i].lastname);
	}

	return 0;
}