Shares of tea company
No.of shares = 2000
FV = Rs.10
MV = Rs.33
Rate of dividend = 25%
S.P of a share = Rs.33
S.P of 2000 shares = 2000 x 33 = Rs. 66,000
Shares of cotton textiles
Investment = Rs. 66,000
FV = Rs. 25
MV = Rs. 44
Dividend =15%
(i) Number of cotton textile shares
= \(\frac {\text{ Investment} }{ M.V } \)
=  \(\frac { 66,000 }{ 44 } =1500\)
(ii) Income from tea company shares
= 2000 x 10 x \(\frac { 25 }{ 100 } \) = Rs. 5000
Income from cotton textiles shares
= 1 500 x 25 x \(\frac { 15 }{ 100 } \) = Rs. 5625
Change in his dividend income = 5625 - 5000 = Rs. 625

\(\text {(i) Number of shares }=\frac{\text { Investment }}{M \cdot V}\)
\(=\frac{8000}{80}=100\)
\(\text {Amount of dividend }=100 \times 100 \times \frac{7}{100}= 700\)
\(\text {(ii) SP of } 100 \text { shares }=75 \times 100= 7500\)
\(\text {Investment }=\mathrm{SP}+\text { Dividend }\)
\(=7500+700= 8200\)
\(\text {Income }=\frac{\text { Investment }}{\mathrm{M} . \mathrm{V}} \times \mathrm{FV} \times \text { Rate of dividend }\)
\(=\frac{8200}{41} \times 25 \times \frac{18}{100}= 900 \text {. }\)
\(\text {(iii) Increase in his return }=900-700\)
\(\text { = } 200\)
\(\% \text { of increase in return }=\frac{\text { Increase in return }}{\text { Investment }} \times 100\)
\(=\frac{200}{8000} \times 100=2.5 \% \)

Machine A:
Present value of out flow = Rs.15,000
a = Rs. 4000, i = 8/100 = 0.08, n = 4
P = \(\cfrac { a }{ i } =\left[ 1-\left( 1+i \right) ^{ -n } \right] \)
\(=\frac{4000}{0.08}\left[1-\frac{1}{(1.08)^4}\right]\)
= 50000 [1 -(1.08)^-4]
= 50000 [1 -0.7350] = Rs.13240
Present inflow is less then present outflow 
Net outflow = 15,000 - 13,250 = Rs.1750.
Machine B
a = 7000, i = 0.08, n = 7
P = \(\cfrac { a }{ i } \left[ 1-\left( 1+i \right) ^{ -n } \right] \)
= \(\cfrac { 7000 }{ 0.08 } \left[ 1-\left( 1.08 \right) ^{ -7 } \right] \)
= 87500(1-0.05835)
= 87500 x 0.4165 = Rs.36,443.75
Present inflow is more than present outflow.
Net inflow = 36,443.75 - 20000
= Rs. 16,443.75
Machine Ycan be purchased.

Given a = Rs. 3000, i = 0.05, n = 4
P = \(\frac { a }{ i } \left[ 1-\left( 1+i \right) ^{ -n } \right] \)
\(=\frac { 3000 }{ 0.05 } \left[ 1-\left( 1.05 \right) ^{ -4 } \right] \)
= 60,000 [1 - 0.8226]
= 60,000 x 0.1773
= Rs.10,638
\(\therefore\) Cash down price = 5000 + 10,638 = Rs.15,638

Let investment in 6% stock be x
\(\therefore\) Investment in 5% stock = 13,500 - x.
At 6% stock
If Investment = 140, Income = 6
If Investment = x, Income \(=\frac { 6x }{ 140 }=\frac { 3x }{ 70 } \)
At 5% stock
If Investment = 125, Income = 5
If Investment = 13,500 - x,
Income = \(\frac { 5(13,500-x )}{ 125 } \)  
\(=\frac { 13,500 -x}{ 25 } =540-\frac { x }{ 25 } \)
Total income = 560
\( \frac { 3x }{ 70 } +540-\frac { x }{ 25 } =560\)
\(\frac { 3x }{ 70 } -\frac { x }{ 25 } =20\)
\(\frac { 15x-14x }{ 350 } =20\) 
x = 350 x 20 = Rs. 7000
\(\therefore\) Amount invested in 6% stock = Rs. 7000
Amount invested in 5% stock = 13500 - 7000
= Rs. 6500