A man bought 40 shares of Tk. 60 at 5 discount, the rate of dividend being 12(1/2)%. The rate of interest obtained is -

Face Value of a share = Tk. 60
He bought each share at Tk. 60 - Tk. 5 = Tk. 55
Number of shares = 40
Dividend = 12(1/2)%
= (25/2)%

Dividend per share = (60 × 25)/(2 × 100)
= Tk. 7.5

Total dividend = (40 × 7.5)
∴ He got a dividend of (40 × 7.5) for an investment of Tk. (40 × 55)

Interest obtained
= (40 × 7.5 × 100)/(40 × 55)
= 13.64%