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Homework Help: Lateral Area and Volume of a Pyramid

  1. Jan 11, 2010 #1
    1. The problem statement, all variables and given/known data
    A square pyramid has a slant height of 25 m and a lateral area of 350 m2. Which is closest to the volume of the pyramid?

    2. Relevant equations

    A = 2sb+b^2
    V = SQRT(2)/6*b^3

    3. The attempt at a solution

    350 = 2 (25) b + 0 -> b = 7m (B^2 is 0 since it is lateral area only)

    V = SQRT(2)/6*(7)^3 = 80m^3

    This answer is not an option but I cant seem to find the error.
     
  2. jcsd
  3. Jan 11, 2010 #2
    You found the right b, but you have the wrong volume formula. V=(1/3)(b^2)(h), where h is the height perpendicular to the base.
     
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