It normally takes 5 hours to drive to the mountains using the main road. John decides to take a shortcut and save 40 minutes. Unfortunately, heavy storms force him to reduce his speed by half for the first half of the trip. How long does it take him to reach the mountains?

If johns destination at first when he was covering it in 5 hours of drive was 150 km, then lets say that he finds a short cut that it is about a 100 km in total distance from its initial point and with the speed of 40 km's, while at first 20 km's he will be driving at 20 km's due to a storm. So, now doing the simple math for it we will get the whole results for the problem, which are given as below:

Explanation:

the answer your looking for is c. : )