7th Grade Geometry

7th Grade GeometryCalculating Surface Areas and Volume in the Real World

PrismA three dimensional solid that has two congruent and parallel faces that are polygons. The remaining faces are rectangles. Prisms are named by their bases.Surface AreaThe sum of the areas of all of the faces of a three dimensional shape.VolumeThe amount of space within the solid.Vocabularyhttp://www.pdesas.org/module/content/resources/6173/view.ashx 2D and 3D shapes2-DTwo measurements length and width.No volume.3-DThree measurements length, width and height.Has a volume (L x W x H)http://www.learner.org/interactives/geometry/area_surface.html http://www.learner.org/interactives/geometry/area_volume.html complete exercise.SolidLengthWidthHeightSurface AreaVolume3 in.5 in.2 in.

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232(5 x 3) + 2(2 x 3) + 2(5 x 2) = 62in5 x 2 x 330in12 cm4 cm2 cmCalculating Surface Area and Volume

3in5in.12cm.2in.4cm.2cm.Area of the baseLengthWidthHeightSurface areaVolume4628848314622946532Find the surface area and volume of the rectangular prisms:Surface area and volume answer key: 38-12, 56-24, 228-216, 62-305Real world applicationList some real world situations where you would need to calculate surface area or volume

Group Exercise Time!In small groups find the dimensions of the room and answer the following questions:If we wanted to paint the walls and knew that one can of paint covers 350 ft, how much paint would we need to buy?How much would it cost to carpet the floor if it cost $20 per ft?

Comparison time.Which group would be the best group to hire to carpet or paint the room? Why?

How much air is in a soccer ball which has a diameter of 8.65inches. (remember to find the volume of a sphere use 4/3 r, where r is the radius or half the diameter)Exit question:

PA state standards:

2.3.6.FEstimate and verify measurements of length, perimeter, area, volume, capacity, temperature, time, weight, and angles.2.3.8.CCalculate volume, surface area, and degrees of angles; calculate circumference and area of circles, and use a measurement formula to solve for a missing quantity.