Wikipedia:Reference desk/Archives/Mathematics/2014 March 21

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March 21

Questions in Unit-Conversions

1. How much Liters there are in 12.6cm^3? It's not homework! I just want to understand how would you even address such a question? (you can change the numbers if you want...)

2. Is there any formula to work with in this "type" of questions? (what about this formula?)

3. Does the aforementioned question is differs anyway from a question like "How much are 15.6ml from 90dl"? (seems like a typical division question doesn't it?) if indeed there is difference, what is it?

Thanks for all the help. 109.64.137.68 (talk) 20:52, 21 March 2014 (UTC)

One litre = 1000 cm³ = 1000 millilitres (ml) = 10 decilitres (dl). —Tamfang (talk) 21:13, 21 March 2014 (UTC)

The question "How much are 15.6ml from 90dl" sounds more like a badly-phrased subtraction question to me. Dbfirs 07:26, 22 March 2014 (UTC)

Concur... if it is meant as a subtraction, i.e. how much is left if 15.6 mL is removed from 90 dL, then noting that 1 dL = 100 mL, the answer is 9000 − 15.6 = 8984.4 mL = 89.844 dL, though 90 dL (2 sig. fig.) would also be a reasonable answer.

If it is meant to be a proportion, i.e. what proportion of 90 dL is 15.6 mL, then the answer is 15.6 / 9000 = 13 / 7500 as a fraction or 15.6 / 90 = 0.17 % (2 sig. fig.)

With the first question, remember that volume consists of three distance dimensions and so litres must equate to some region in cubic metres, and the litre is defined as 1 L = 1000 cm³ so 1 mL = 1 cm³. EdChem (talk) 07:53, 22 March 2014 (UTC)

What about the second and third questions. can someone please kindly take a look? 109.64.137.68 (talk) 17:52, 22 March 2014 (UTC)

How do the answers already given to the third question leave you unsatisfied?

The Youtube lesson is accurate. It could stand to say a bit more explicitly that the method works because the quantity in parenthesis is equivalent to 1. —Tamfang (talk) 00:25, 23 March 2014 (UTC)

Sorry, I confused. They did answer. How did this guy had 2.2 at the denominator ? How did he got it? 95.35.60.188 (talk) 07:59, 23 March 2014 (UTC)

1 kilogram = how many pounds? —Tamfang (talk) 08:10, 23 March 2014 (UTC)

Sorry I'm not familiar with ppunds and I dont have a way to check it. 95.35.60.26 (talk) 08:45, 23 March 2014 (UTC)

See Pound (mass), but they are not much used outside America and Britain. Dbfirs 09:06, 23 March 2014 (UTC)