FAC.G.38
Fluently use formulas and/or appropriate measuring tools to find length and angle measures, perimeter, area, volume, and surface area of polygons, circles, spheres, cones, cylinders, pyramids, and composite or irregular figures. Use them to solve real-world and mathematical problems. (8.G.9)
Example Problems
A circle has a circumference of 31.4 units.
What is the radius of the circle?
Use 3.14 for π.
What is the radius of the circle?
Use 3.14 for π.
A circle has a circumference of 15.7 units.
What is the radius of the circle?
Use 3.14 for π.
What is the radius of the circle?
Use 3.14 for π.
A circle has a circumference of 439.6 units.
What is the radius of the circle?
Use 3.14 for π.
What is the radius of the circle?
Use 3.14 for π.
Khan Academy ResourcesVolume formulas reviewVolume of a pyramid or coneCavalieri's principle in 3DCavalieri's principle in 2DVolume of composite figuresVolume and surface area of cylindersApply Cavalieri's principleUse related volumesVolume of prisms and pyramidsApply volume of solidsDensity word problemsVolume of a sphereVolume of triangular prism & cubeCylinder volume & surface areaVolume of pyramids intuitionUsing related volumesArea of a circle intuitionVolume of a coneCavalieri's principle in 3DApplying volume of solidsVolumes of cones intuition

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