You have to divide 355 km by 7 hours and you will get the hour rate then multiple the hour rate by I.5 which it the extra hours you will travel for. After you get the answer of the amount of km in 1.5 hours add 355 to it. Thus, arriving to the solution of traveling 431.0714285714286km in 8.5 hours. You can round it to 431.1 km.
