In the middle of the confounded desert, there is the lost city of “Ash”. To reach it, you will have to travel overland by foot from the coast. On a trek like this, each person can only carry enough rations for five days and the farthest we can travel in one day is 30 miles . Also, the city is 120 miles from the starting point.

What is the fewest number of persons (including yourself) that you will need in your Group to accomplish this mission, so that you can reach the city, stay overnight, and then return to the coast without running out of supplies.

The answer is an integer . Just put the number without any decimal places.