Posted by JP on .
An antelope has traveled 1.60 km at avg speed of 67.0 km/h. The antelope speed during the first half of the distance is 88km/h. Find the antelope's avg speed during the second half of the run.

Physics 
Steve,
The time is the distance divided by the velocity. The total time is the time at 88km/h + the time at the unknown speed v. Half the distance is run at each speed:
0.8/88 + 0.8/v = 1.6/67
.009091 + 0.8/v = .02388
.8/v = 0.01365
v = 58.6 km/h