If x is the total number of shares and each share has a face value of R100, then the true value of the 96 share will be R96 and the share at par will be R100. So x/2 of the 96 shares will fetch 5% in income=0.05x/2 * 96=2.4x.
And x/2 of the par shares will fetch 0.06x/2 * 100=3x.
The total income is therefore 5.4x.
Now, x shares at R108 per share at 6.75% fetch 0.0675 * 108=7.29x.
The difference is (7.29-5.4)x=1.89x=R41.67. So x=22.05 (12500/567) and the investment is R2205 (1250000/567=R2204 332/567).
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