∆ PQR is right angled at Q. If m∠R = 60°, what is the length of PR (in cm), if RQ = 4√3 cm?
cos60°= $$\frac{QR}{PR}$$
$$\Rightarrow \frac{1}{2}=\frac{4\sqrt{3}}{PR}$$
$$\Rightarrow PR = 8\sqrt{3}$$
so the answer is option D.
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