0.62068966 or 18/29 depending on how you want to set it up.
To make a fraction into simplest form you have to find the greatest common factor. In this case it is 5. So then you divide both the numerator and the denominator by the greatest common factor of 5.
15÷5=3
100÷5=20
There is no factors that go into both 3 and 20 so simplest form is 3/20.
The phrase would be: "z divided by the difference of 8 and 9"
The hint says that volume of a rectangular solid = l*w*h, where l = length, w = width, and h = height. Use this to solve for the height of the solid by plugging in the numbers you know.
You know that length, l = 2cm, width, w = 8cm, and, *EDITED* volume = 160 cm^3. Plug these values into the equation for volume (the hint) and solve for h, the height:
Volume = lwh
160 = (2)(8)(h)
160 = 16h
h = 10cm
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Answer: The height is 10 cm