Question #c4e05

1 Answer
Dec 29, 2017

Mark's average speed for the whole journey was #68.2 "km/h"#

Explanation:

These are Mark's times and speeds: Calculate each distance:

3 hours @ 65 km/h . . . .195 km
2 hours @ 73 km/h . . . .146 km
..................................................................
5 hours . . . . . . . . . . . . . . 341 km

#341  "km in " 5  "hours"#

#(341  "km")/(5  "h")#  is an average speed of #68.2  "km/h"#