Question 483190
An automobile traveling at a certain rate can go from one province to another in 9 hours. If the rate were 12 kilometers per hour faster, the trip would require two hour less. What is the distance between provinces? 
-----------------
1st trip DATA:
time = 9 hrs; rate = x kph ; distance = 9x km
---------------
2nd trip DATA:
time = 7 hrs; rate = x+12 kph ; distance = 7(x+12) km
--------------------
Equation:
distance = distance
9x = 7(x+12)
9x = 7x + 84
---
2x = 84
x = 42 
----
distance = 9*42 = 378 km
============================
Cheers,
Stan H.
=============