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Finding the arc length of a sector of a circle when given the radius of the circle and angle of the sector.

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Find the length of the arc for the sector of a circle with radius $r=\\var{r}$ cm and an angle $\\theta=\\frac{\\pi}{\\var{t}}$ radians, giving your answer in terms of $\\pi$.

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To give an answer in terms of $\\pi$ type 'pi', e.g. '2pi'

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To calculate the arc length for a sector of a circle we want to use the formula \\[ s = r \\theta, \\]

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where $s$ is the arc length, $r$ is the radius of the circle, and $\\theta$ is the central angle measured in radians:

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{geogebra_applet('https://www.geogebra.org/m/pbds8nkd')}

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So, if $r=\\var{r}$ cm and $\\theta=\\frac{\\pi}{\\var{t}}$, then

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\\[ \\begin{split} s &\\,= \\var{r} \\times \\frac{\\pi}{\\var{t}} \\text{ cm} \\\\ &\\,= \\simplify[all, fractionNumbers]{{r/t}pi} \\text{ cm}. \\end{split} \\]

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$s=$[[0]] cm

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