(i) Given,
1st Company = 12%, ₹100 shares at ₹125
Investment = ₹50,000
2nd Company = 15%, ₹100 shares at ₹120
Investment = ₹60,000
3rd Company = 18%, ₹100 shares at ₹ 140
Investment = Remaining
Total annual income = ₹ 21,300
For 1st Company :
Number of shares = $\frac{\text{Total investment}}{\text{Market value of each share}} = \frac{50000}{125} = 400$
Annual income = No. of shares × Rate of div. × N.V. of 1 share
= 400 × $\frac{12}{100}$ × 100
= 400 × 12
= ₹ 4,800
For 2nd company :
Number of shares = $\frac{\text{Total investment}}{\text{Market value of each share}} = \frac{60000}{120} = 500$
Annual income = No. of shares × Rate of div. × N.V. of 1 share
= 500 × $\frac{15}{100}$ × 100
= 500 × 15
= ₹ 7,500
Income from first two companies = ₹ 4,800 + ₹ 7,500 = ₹ 12,300
Total annual income = ₹ 21,300
Income from 3rd Company = ₹ 21,300 - ₹ 12,300 = ₹ 9,000
Annual income = No. of shares × Rate of div. × N.V. of 1 share
9000 = No. of shares × $\frac{18}{100}$ × 100
9000 = No. of shares × 18
No. of shares = $\frac{9000}{18}$ = 500
Investment in 3rd company = Number of shares × Market price = 500 × 140 = ₹ 70,000
Total Investment = ₹ 50,000 + ₹ 60,000 + ₹ 70,000 = ₹ 1,80,000
Rate of Return = $\frac{\text{Total income}}{\text{Total investment}} \times 100$
= $\frac{21300}{180000} \times 100$
= 11.83%
Hence, rate of return = 11.83%.
(ii) Investment in 3rd company = Number of shares × Market price = 500 × 140 = ₹ 70,000
Hence, investment in third company = ₹ 70,000.