1. **Problem statement:** A man invests equally in shares of two companies A and B. Company A's shares are priced at a 20% premium on 100 rupees and pay an 8% dividend. Company B's shares are priced at a 10% discount on 100 rupees and pay a 7% dividend. The total dividend income is 936. We need to find the total amount invested.
2. **Understanding the problem:**
- Face value of each share = 100 rupees.
- Price of A's share = 100 + 20% of 100 = 100 + 20 = 120 rupees.
- Price of B's share = 100 - 10% of 100 = 100 - 10 = 90 rupees.
- Dividend rate for A = 8% of face value = 8 rupees per share.
- Dividend rate for B = 7% of face value = 7 rupees per share.
3. **Let the amount invested in each company be $x$ rupees.**
4. **Number of shares bought:**
- Shares of A = $\frac{x}{120}$
- Shares of B = $\frac{x}{90}$
5. **Dividend from each company:**
- Dividend from A = number of shares $\times$ dividend per share = $\frac{x}{120} \times 8 = \frac{8x}{120} = \frac{2x}{30}$
- Dividend from B = $\frac{x}{90} \times 7 = \frac{7x}{90}$
6. **Total dividend = 936:**
$$\frac{2x}{30} + \frac{7x}{90} = 936$$
7. **Find common denominator and solve:**
- Common denominator = 90
- Rewrite: $$\frac{2x}{30} = \frac{2x \times 3}{30 \times 3} = \frac{6x}{90}$$
- So, $$\frac{6x}{90} + \frac{7x}{90} = \frac{13x}{90} = 936$$
8. **Solve for $x$:**
$$13x = 936 \times 90$$
$$13x = 84240$$
$$x = \frac{84240}{13} = 6480$$
9. **Total investment:** Since the man invests equally in both companies, total investment = $x + x = 2x = 2 \times 6480 = 12960$ rupees.
**Final answer:** The man invested a total of 12960 rupees.
Investment Dividend 520F2A
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