a stone is thrown in upward direction. calculate the the velocity by which the stone was thrown when the the covered distance in 5th and 6th sec are equal

To cover equal distance in 5^th and 6^th sec in upward direction stone velocity is 50m/s, because if we want that distance to be equal then stone veocity should be zero between the given time interval. So if velocity of stone is taken 50m/s. then its velocity is zero at t = 5sec and distance covered in 5^th sec is 5m. and after that stone starting falling downwords and in 6^th sec it also covered 5m.