From the top of a tower a body A is thrown up vertically with velocity u and another body B is thrown vertically down with the same velocity u. If vA and vB are their velocities when they reach the  ground and tA and tB are their times of flight, then

Taking all upward physical quantities negative and downward physical quantities positive, for stone A,  (vA)2 = (-u)2 + 2gh and for stone B, (vB)2 = u2 + 2gh  vA = vB  stone A goes up, then comes down and then strikes the earth where as after projection stone B goes down and  directly  strikes the earth therefore tA > tB