Can you kindly explain how the population on 1 Jan 2014 was derived. I thought you would use linear interpolation but I get the wrong answer using the following workings Population on 1 Jan 2014 = \(2 333 +\frac{2}{12}(\frac{2417 - 2 333}{12}) = 2 334.1666\)
I haven't even looked at the question - but why have you got 12 twice in your interpolation? Look at the reasonability of your answer, you want to be 1/6th of the way through the interval, and you're still at the very bottom!
I have recalculated it as follows \(\frac{1}{2}(x + 2 333)\frac{2}{12} + \frac{1}{2}(x + 2 417)\frac{10}{12} = \frac{1}{2}(2 333 + 2417)\) x = 1 Jan gives me the correct answer of 2 347