A metal sleeve of length 20 cm has a rectangular cross section of 10cm by 8cm as shown. The metal has uniform thickness of length X cm along the sleeve, and the total volume of metal sleeve is 495 cm³. 1) what is the total volume of the whole figure?
2) what is the volume of the hollow?
3) what is the length and width of the hollow?
4) derive the equation 16x² — 144x + 99 = 0 , and solve it to find the value of x .
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