The aluminum in a package containing 75 ft2 of kitchen foil weighs approximately 12 ounces. Aluminum has a density of 2.70 g/cm3. What is the approximate thickness of the aluminum foil in millimeters? (1 ounce = 28.4g)

18130 mm

Explanation:

Now we have a lot of unit conversions to do in order to correctly answer this question. We shall do these conversions gradually.

First we convert the weight in ounce to grams.

If 1 ounce = 28.4g

12 ounces = 12*28.4 = 340.8 g

Next we convert the area of aluminum from ft2 to m2

1ft2 = 0.0929 m2

75 ft2 = 75 * 0.0929 = 6.9675m2

Now density of aluminum = 2.70 gcm-3

Density = mass/volume

But volume = area * thickness

Density = mass / area * thickness

Density * area * thickness = mass

Thickness = mass / density * area

Thickness = 340.8g / 2.70gcm-3 * 6.9675m2

Thickness = 340.8/18.8

Thickness = 18.13 m

Since 1000 milimeters make 1 metre

Thickness = 18130 mm