A rectangle of side 8 cm × 6 cm and a rhombus (side = 8 cm, acute angle 60°) are joined along one 8 cm side. What's the ratio of their areas (rectangle : rhombus)?
\(\sqrt{3} : 2\)
Area of the rectangle = 8 × 6 = 48 cm2.
Area of a rhombus = \(a^2 \sin\theta = 8^2 \times \sin 60^\circ = 64 \times \frac{\sqrt{3}}{2} = 32\sqrt{3}\) cm2.
Ratio = \(48 : 32\sqrt{3} = 3 : 2\sqrt{3}\). Dividing both terms by \(\sqrt{3}\) gives \(\sqrt{3} : 2\).
Hence, the ratio of the areas (rectangle : rhombus) is \(\sqrt{3} : 2\).
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