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Density equation problem

  • Thread starter jle1092
  • Start date
  • #1
The density of a certain type of plastic is 0.75 g/cm^3. If a sheet of this plastic is 10.0 m long, 1.0 m wide, and 1 cm thick, what is its mass?

Density= m\V
V= l x w x h

Rearranged the equation so that M = DV

m=(.75 g/cm^3)(100,000 cm^3)

and got m=75,000 g or 7.5 x 10^4 g.

I was wondering if I did the problem correctly, also, if it is in proper units? Thank you.

Answers and Replies

  • #2
Homework Helper
Education Advisor
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Also, note you should use a forward slash for text to indicate the fraction bar, D=m/V.
You showed the backslash.
  • #3
Im looking at the same question in my chem book right now. Just also remember sig figs. When multiplying you must take the LEAST accurate piece of data to figure out your sig figs for your answer. In this case the least accurate piece of data would be 1 cm, which is 1 sig fig. So technically your answer should be rounded up to 8 x 10^4