Calculate the total distance you traveled, if:
You left home at 10 a.m. and walked 500 m to a friend's house. At 11, you all drove 5 km to the mall.
At 1:30, your friend drives you 4 km to your house. The total distance you traveled, round trip, is ___.
Unnecessary info about times taken to travel to places. All that you need to do is SUM the distances: 500 m + 5 km + 4 km.
You should notice that the distances are NOT in the same unit, and so, you have to convert from one to the other, and then SUM them.