Two trans on opposite tracks leave the same station at the same time. One train travels at an average speed of 80 kilometers per hour and the other train travels at an average of 70 kilometers per hour. How long after the leave the station will they be 50 kilometers apart

The means and mean absolute deviations of the individual times of members on two 4x400-meter relay track teams are shown in the table below. means and mean absolute deviations of individual times of members of 4x400-meter relay track teams team a team b mean 59.32 s 59.1 s mean absolute deviation 1.5 s 245 what percent of team b's mean absolute deviation is the difference in the means? 9% 15% 25% 65%