The army messenger will travel at the speed of 60 miles per hour on land and in the motorboat whose speed is 20 miles per hour in still water. In delivering the message he will go by land to the dock on the river and then on river against the current of four miles per hour. If he reaches the destination in 4 1/2 hours and then returns to the starting point in 3 1/2 hours, how far he traveled by land and how far by water.