The graph showes you the percent CHANGE in the students in 2015 +11% and then in 2017 a decrease of 3%

I do not see any wrong wording in the question sir.

It perhaps needs more clarification - the percent change relative to the previous year? why do we multiply 1.11 with 1000? I set this up as 1.11x=1000, so the number of students in philosophy would be 1000/1.1, 3 percent decrease would then correspond to .97(1000/1.11)

I don't think we can calculate the answer based on the given data. assuming 11% in 2015 means the #student increase by 11% from 2014 to 2015; if this is the case, then -3% in 2017 mean, it dropped 3% from 2016 to 2017 which we still do not have the number of students in 2016.

Another scenario is that 11% in 2015 mean it risen 11% from 2015 to 2016. Then, coherently, -3% in 2017 column should mean it dropped 3% from 2017 to 2018 meaning than we still don't have %change to calculate 2016 to 2017

Carcass

Not sure.

For me having two years 2015 and 2017 that 11 % is a rise inevitable from at most the previous year 2014 because the % change is always from the actual point and the previous one.

The second scenario I think is unlikely

But probably that's me