SEAMO 2027 - Paper E - SET 06 - Self-study Question 20

In the figure, $AB$ and $CD$ are parallel chords of a circle with centre $O$ and radius $r\text{ cm}$. Given $AB=46\text{ cm}$, $CD=18\text{ cm}$ and $\angle AOB=3\angle COD$, find $r$.



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