ACT Preparation / Unit 14 ACT 1311 short lesson, about 20 seconds
Rectangular Solids
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The idea
A rectangular solid's volume is length times width times height, in cubic units. Its surface area is the total area of its six faces: 2lw + 2lh + 2wh.
In practice
A 5-by-3-by-2 box has volume 30 and surface area 2(15 + 10 + 6) = 62.
Where people slip
Volume fills; surface area covers. They use different units and different formulas.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
Builds on
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