Help understanding metric units

[tomtomtom1]

Hi all

Firstly this is not a homework question. I just found myself wondering what certain numbers meant while at work and realized that i didnt actually know hence the posting.

I was hoping someone could help explain & confirm a couple of things about units.

1) Given the number 4.172 meters
I interpret this number at 4 whole meters
And the 0.172 part I interpret as a portion of a whole meter
My first question is this; is 0.172 (the fractional part) still in meters or is this in cm?

2) Assuming that 0.172 is in meter then to understand the 0.172m a little better I have done the following:-

1 ● 1 / 10 1 / 100 1 / 1000
0 ● 1 7 2

I have re-writtern this fractional part as 172/1000

My understanding at this point is that the denomniator (1000) represents my whole meter and the numerator represents the portion of the whole meter
Is this correct?


Attached is a PDF document where i have tried to understand more about units which i was hoping someone could look at.

 

[mfb]

1) Given the number 4.172 meters
I interpret this number at 4 whole meters
And the 0.172 part I interpret as a portion of a whole meter
My first question is this; is 0.172 (the fractional part) still in meters or is this in cm?

If I give you 1/2=0.5 apples, I give you 1/2 of an apple and not 1/2 of [something else].
If I give you 3.5 apples, I give you 3 apples and 1/2 apple and not 3 apples and 1/2 of [something else].

2) Assuming that 0.172 is in meter then to understand the 0.172m a little better I have done the following:-

1 ● 1 / 10 1 / 100 1 / 1000
0 ● 1 7 2

I have re-writtern this fractional part as 172/1000

My understanding at this point is that the denomniator (1000) represents my whole meter and the numerator represents the portion of the whole meter
Is this correct?

It is correct, and you can get the same just with rewriting the numeric value:
3.172 meters = (3172/1000) meters = (3 + $\frac{172}{1000}$) meters