Anonymous
Anonymous asked in Science & MathematicsChemistry · 9 years ago

how come when i convert his i get .0015 cm , but the internet says 15 cm? this is what i did-

150 mm x 0.001m/1mm x 0.01cm/1m = .0015 cm

Update:

why are you guys using 100 and 10? i thought milli and centi were 10^-3 and 10^-2 ?

Relevance

You are trying to convert mm to cm so you don't need to reference the m measurement at all

10mm is 1 cm so 150/10 would give you 15cm.

I'm not really sure what you were doing with your calculations there but the closest I can come up with was that you were trying to convert all your measurements to the same type. If you're wanting to convert it to m first, then you would do the first portion of your calculation:

150mm X .001m which would give you 150mm in m equaling .15m

150 X .001 = .15

So now you have your mm converted into m.

Then you would have to convert that into cm. So...

.15m * 100cm which gives you 15cm.

.15 * 100 = 15

You don't need to convert the mm to m then the cm to m and then divide it by 1 m to get the right answer. You are just overly complicating things. Remember that the metric system is very simple in that everything is in 10's. 1/10th of a meter is a deci, 1/10th of a deci is a centi, 1/10th of a centi is a milli, etc.so when converting to meters you multiply by the 1/10, 1/100, 1/1000. The conversion turns it into that unit of measure.

What I think you mistook in the second section of your equation was that you were trying to convert using a m and cm ratio (0.01) which is not how that works. To convert from mm to cm it is only one 1/10 tier meaning (.1). So 150mm X .1cm would also equal 15cm.

150 X .1 = 15

I tried showing you three ways to work this problem. I was trying to figure out how you were trying to work it to keep with your current train of thought, but I'm not 100% on how you were trying to do it. I hope this helps you understand it better. Good luck with future conversions.

• 150 mm /10 = 15 cm.

• You did it right except for the final step. It should be 100cm/m (100 cm = 1 m) Hundreds, not hundredths.

Otherwise, you have it set up correctly. You could also use 1cm/0.01m (same thing, but your 0.01 is on the bottom, not the top). That will give you the right answer.

• the rule is from small to big divide, so divide by 10=15.0cm or b/c 10mm=1cm we get , 150/10=15.0 cm