cubic meter

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cubic meter

by baller12q » Tue Mar 31, 2009 3:27 pm
The mass of 1 cubic meter of a substance is 800 kilograms under certain conditions. What is the volume, in cubic centimeters of 1 gram of this substance under these condition (1 kilogram= 1000 grams and 1 cubic meter = 1,000,000 cubic centimeters.

a. .80
b. 1.25
c. 8.00
d. 12.50
e. 80.00


how do i solve

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by Jose Ferreira » Tue Mar 31, 2009 7:29 pm
Hi,

In this question, we are given information in terms of cubic meters and kilograms, and asked for an answer in terms of cubic centimeters and grams.

The proportion that the question tells us is:
1 cubic meter/800 kilograms = x cubic centimeters/1 gram

We will need to convert kilograms to grams, and cubic meters to cubic centimeters. We will first convert the left side to cubic centimeters and grams, then solve for x.

We are told that 1 kilogram = 1000 grams and 1 cubic meter = 1,000,000 cubic centimeters.

To convert units, we must multiply by quantities that are equal to 1, so that we do not alter the fundamental value. In this case, we can multiply by 1 kilogram/1000 grams or 1000 grams/1 kilogram, because these fractions are both equal to 1. That is, 1000 grams = 1 kilogram.

To convert 1 cubic meter to cubic centimeters, multiply by 1,000,000 cubic centimeters/1 cubic meter. It is important to put 1 cubic meter in the denominator of the fraction, so that the cubic meter terms cancel out and we are left with cubic centimeters.

1 cubic meter * 1,000,000 cubic centimeters/1 cubic meter = 1,000,000 cubic centimeters.

Similarly,
800 kilograms * 1000 grams/1 kilogram = 800,000 grams.

So, 1 cubic meter/800 kilograms = 1,000,000 cubic centimeters/800,000 grams. This reduces to 1.25 cubic centimeters/1 gram.

Since we are looking for x in the expression (x cubic centimeters/1 gram), the answer is 1.25.
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Re: cubic meter

by marcusking » Wed Apr 01, 2009 5:27 am
baller12q wrote:The mass of 1 cubic meter of a substance is 800 kilograms under certain conditions. What is the volume, in cubic centimeters of 1 gram of this substance under these condition (1 kilogram= 1000 grams and 1 cubic meter = 1,000,000 cubic centimeters.

a. .80
b. 1.25
c. 8.00
d. 12.50
e. 80.00


how do i solve
Since we know that 1 cubic meter = 1,00,000cc and 1Kg = 1000g I just converted the mass of the substance to be in these terms so:

1000000cc = 800000g(k) now I just cancel zeros from both sides to get
10=8(k)
k = 1.25