(i) Explain the census approximation for calculating the exposed to risk between any two census dates. [2] A mortality investigation bureau has collected the following information on number of policies in-force each year from different companies. Age and year Year Company A Company B Company C Age 54 2011 3,400 1,250 5,780 2012 3,350 1,450 5,500 2013 3,000 1,500 6,010 Age 55 2011 3,250 1,190 6,000 2012 3,390 1,300 5,960 2013 3,100 1,440 6,030 Age 56 2011 3,270 1,150 5,950 2012 3,020 1,300 5,980 2013 2,950 1,500 5,990 . Company A has provided in-force policy data as at the beginning of each calendar year using age nearest birthday. Company B has provided in-force policy data as at the financial year closing date (which was 31 March in each year) using age last birthday. Company C has provided in-force policy data as at the end of each calendar year using age next birthday. (ii) Calculate the contribution to central exposed to risk for lives aged 55 last birthday for the calendar year 2012 for each of the companies. [6] [Total 8]