The angle in one regular polygon is to that in another as \(3:2\) and the number of sides in the first is twice that in the second. Determine the number of sides of the two polygons.

Solution:

Let the number of sides of the second polygon be \(n\).

Then the number of sides of the first polygon is \(2n\).

Interior angle of a regular polygon:

\[ \frac{(n-2)\times180^\circ}{n} \]

First polygon angle:

\[ \frac{(2n-2)\times180^\circ}{2n} \]

\[ =\frac{(n-1)\times180^\circ}{n} \]

Second polygon angle:

\[ \frac{(n-2)\times180^\circ}{n} \]

Given ratio:

\[ \frac{(n-1)\times180^\circ}{n} : \frac{(n-2)\times180^\circ}{n} = 3:2 \]

\[ \frac{n-1}{n-2}=\frac{3}{2} \]

\[ 2(n-1)=3(n-2) \]

\[ 2n-2=3n-6 \]

\[ n=4 \]

Therefore,

Second polygon has \(4\) sides.

First polygon has \(2n=8\) sides.

Hence, the polygons are:

\[ \text{Quadrilateral and Octagon} \]

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