Question 980670: on a journey of 375 km , a motorist travels part of the journey on a expressway a 95 km/h and he rest at 65 km/h. the total time he spends on the stretch of road at 65 km/h is twice the time he spends on the expressway . how long did he take for thr whole journey?
Answer by josgarithmetic(39625)   (Show Source):
You can put this solution on YOUR website! __________________rate____________time____________distance
expressway________95_______________t______________(____)
regular___________65______________2t______________(____)
Total_____________________________3t________________375
RT=D uniform rates travel relating rate, time, distance.
__________________rate____________time____________distance
expressway________95_______________t______________95t
regular___________65______________2t______________65*2t
Total_____________________________3t________________375
Solve for t and evaluate 3t.
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FURTHER STEPS WANTED FOR BETTER UNDERSTANDING
The "distance" column shows the sum of terms for distance expressions, so this gives us the distance sum equation:
This one equation uses only a single variable,  . Solve for t.
 , time in hours.
THE TIME SUM Column shows that total time was  .
Knowing  , we can compute the total travel time,  .
Distances for each road type were also unknown, each based on the time t, which has now been found (solved).
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Expressway,  .
Regular road,  .
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