Answer:
Duration of the tour he planned first is 8 days.
Explanation:
Given that a person has 12000 rupees for his daily expenses.
Let x be the number of days.
Then daily expenses per day

Given that number of day is increased by 2 more days, that is number of days is x+2.
New daily expense per day

Given that this new daily expenses are 300 less than original.
That is





(x-8)(x+10)=0
x=8 or -10.
Since number of days cannot be negative, duration of the tour planned=8.