HELP

[Coopermoody]

Can someone please help me with this question, dont know what im doing wrong answer is apparently D

[Stick]

First of all, we must determine the mean for the two groups in which 1995 is in the 'middle' (ie when it is second or third in a group of four).

Average of years 93-96: (13+7+3+9)/4 = 8
Average of years 94-97: (7+3+9+10)/4 = 7.25

These values are not centred on 1995 (they are between 1994 and 1995, and 1995 and 1996 respectively). Now we take the average of these values to centre the data on 1995.

(8+7.25)/2 = 7.625

[Coopermoody]

Thanks