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Factor volume changed

  1. Jan 15, 2012 #1
    1. The problem statement, all variables and given/known data

    Initially, A yoga ball is partially blown up and its surface area measured. Afterwards, it is filled completely and its surface area is found to be 1.50 times as big as it was recorded earlier. By what factor has its volume changed?

    Im not sure how to solve for this? can someone explain please

    3. The attempt at a solution
  2. jcsd
  3. Jan 15, 2012 #2


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    Gold Member

    First write down any formulas that you think might help,

    Surface area of sphere S = 4*∏*r^2

    Volume of a sphere V = [4*∏*r^3]/3

    Write down what you know, S2 = 1.5*S1 or

    4*∏*r2^2 = 1.5*4*∏*r1^2 simplify and use this to find,

    what you want to know, F*V1 = V2 or F = V2/V1 = ? Use the above expression for volume to write out and simplify V2/V1.

    Does this get you started?
  4. Jan 16, 2012 #3
    No, I dont understand your steps of what to do.
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