Answer:
a) Let the catchup takes place at the age of X years from the time when they are 62 years of age. Then their accumulated benefits will be
(X - 62)*1500 = (X - 66)*2000
1500X - 93000 = 2000X - 132000
500X = 39000
This gives X = 78. Hence at the end of 77 years or in the beginning of 78 years of age, the accumulated benefits will be equal independent of when they start
b) When the interest rate is 6%, PW is given by
PW(early starters) = 1500*(P/A, 6%, (85 - 62)) PW(late starters) = 2000*(P/A, 6%, (85 - 66))
= 1500*12.3034 = 18455.1 = 2000*11.1581 = 22.316.2
Hence, present worth of second plan of strating late has a higher PW.
Explanation: