✔ 最佳答案
Let $D be the annual deposit from the fifth birthday to the fifteen birthday
Present value of the deposit = $D x {1 – [(1 + 8%) ^ (-11)]} x (1 + 8%) / 8%
Present value of the withdrawal from the eighteen birthday to the twenty-second birthday = $20,000 x {1 – [(1 + 8%) ^ (-5)]} x (1 + 8%) / {8% x [(1 + 8%) ^ 13]} = $20,000 x {1 – [(1 + 8%) ^ (-5)]} / {8% x [(1 + 8%) ^ 12]}
Hence,
$D x {1 – [(1 + 8%) ^ (-11)]} x (1 + 8%) / 8% = $20,000 x {1 – [(1 + 8%) ^ (-5)]} / {8% x [(1 + 8%) ^ 12]}
$D = $20,000 x {1 – [(1 + 8%) ^ (-5)]} / {1 – [(1 + 8%) ^ (-11)]} / [(1 + 8%) ^ 13] = $20,000 x 0.3194 / (0.5711 x 2.7196) = $20,000 x 0.2056 = $4,112.95
Birthday
Cash Flow
Discounted Cash Flow
5
-$4,112.95
-$4,112.95
6
-$4,112.95
-$3,808.29
7
-$4,112.95
-$3,526.19
8
-$4,112.95
-$3,264.99
9
-$4,112.95
-$3,023.14
10
-$4,112.95
-$2,799.21
11
-$4,112.95
-$2,591.86
12
-$4,112.95
-$2,399.87
13
-$4,112.95
-$2,222.10
14
-$4,112.95
-$2,057.50
15
-$4,112.95
-$1,905.09
18
$20,000.00
$7,353.96
19
$20,000.00
$6,809.22
20
$20,000.00
$6,304.83
21
$20,000.00
$5,837.81
22
$20,000.00
$5,405.38
S
$0.00