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    A towel has a volume of 6100 cm3
    The towel shrinks in a tumble drier. It remains a similar shape but its surface area decreases by 12%.
    Find the new volume of the towel (to 3 sig. figs.)

    - I don't know how to work out the original surface area in order to work out the scale factor, so that I can then work out the new volume... (If this is the correct logic behind working out this question)

    Thank you
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    (Original post by RosaA)
    A towel has a volume of 6100 cm3
    The towel shrinks in a tumble drier. It remains a similar shape but its surface area decreases by 12%.
    Find the new volume of the towel (to 3 sig. figs.)

    - I don't know how to work out the original surface area in order to work out the scale factor, so that I can then work out the new volume... (If this is the correct logic behind working out this question)

    Thank you
    You don't need to. If the linear scale factor is s then the area scale factor is s^2 and the volume scale factor is s^3.

    Here you have s^2 = 0.88, so what's the volume scale factor?
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    (Original post by Zacken)
    You don't need to. If the linear scale factor is s then the area scale factor is s^2 and the volume scale factor is s^3.

    Here you have s^2 = 0.88, so what's the volume scale factor?
    So, if
    s^2 = 0.88
    s = 0.938083152

    Volume = s^3
    s^3 = 0.938083152^3
    =0.8255131737

    6100 cm^3 x 0.8255131737 = 5035.63036 cm^3
    = 5035.63 cm^3 (3 sig. figs.)

    It this answer correct?
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    (Original post by RosaA)
    So, if
    s^2 = 0.88
    s = 0.938083152

    Volume = s^3
    s^3 = 0.938083152^3
    =0.8255131737

    6100 cm^3 x 0.8255131737 = 5035.63036 cm^3
    = 5035.63 cm^3 (3 sig. figs.)

    It this answer correct?
    looks right
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    (Original post by Zacken)
    looks right
    I just realised, I made a mistake when changing the answer to 3 sig. figs. -sorry
    It should be 5036 cm3

    Thank you for the help!
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    (Original post by RosaA)
    I just realised, I made a mistake when changing the answer to 3 sig. figs. -sorry
    It should be 5036 cm3

    Thank you for the help!
    no problem!

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