Sgu/144

极简单的概率题 分两种情况讨论

//by hza
#include<cstdio>
 
double x,y,z,dist;
 
int main()
{
	freopen("144.in","r",stdin);
	freopen("144.out","w",stdout);
	scanf("%lf%lf%lf",&x,&y,&z);
	z=z/60;
	dist=y-x;
	printf("%.8lf\n",(dist-z)/dist*z/dist*2+z*z/dist/dist );
}