Please explain why we are not using Deferred annuity here. Also, in solution where D' is mentioned what does this ' represents.
D' is the formula for deferred function of the solution. It actually is represented by Day, here it is simply written as D'. Its values are given in tables page 84-85. [(v^n)*npx]=D(X+n)/Dx Where n is the time period of survival before annuity starts, x is the current age, p is the probability of survival, i.e. npx is the probability that a person ahead x will survive for another n years and die between n and n+1 years. v^n is the discounting function as studied in CT1. Deferred annuity has been used here. It is as given in the page 20 of chapter 2 (2016 material) on the last page of topic 6. Hope this helps! Regards, Shyam
