Answer:
Part A:
[tex]PV=\$760662.5271[/tex]
Part B:
Money saved by age 60:
[tex]FV=\$382714.3014[/tex]
Part C:
Money spend each year:
[tex]C=\$38980.29695[/tex]
Explanation:
Part A:
The formula for Growing Annuity is given by:
[tex]PV=C[\frac{1}{r-g}-\frac{1}{r-g}(\frac{(1+g)^T}{(1+r)^T)}][/tex]
Where:
r is discount rate
g is increase per annum
T is time
C is salary
[tex]PV=\$40,000[\frac{1}{0.08-0.05}-\frac{1}{0.08-0.05}(\frac{(1+0.05)^{30}}{(1+0.08)^{30}})]\\PV=\$760662.5271[/tex]
Part B:
PV of salaries*0.05=$38033.1264 (PV calculated in Part A)
FV(Money Saved)=[tex]PV(1+r)^T[/tex]
[tex]PV(1+r)^t\\FV=\$38033.1264(1+0.08)^{30}\\FV=\$382714.3014[/tex]
Part C:
[tex]PV=C[\frac{1}{r}-\frac{1}{r*(1+r)^t}][/tex]
Where
C is savings spend each year
r is the interest Rate
t is time= 20 years
PV as FV calculated in Part B
[tex]\$382714.3014=C[\frac{1}{0.08}-\frac{1}{0.08-(1+0.08)^2^0}]\\C=\$38980.29695[/tex]