Which value represents one part of a thousand?

The value that represents one part of a thousand is 0.001. This is because the term "one part of a thousand" refers to the fractional value of one divided by one thousand. When you perform this division (1 ÷ 1000), you get 0.001.

In decimal form, this means that if you have a whole (1.000), one part of a thousand is equal to one thousandth of that whole. This is often used in various contexts, such as in measurements, concentrations, and comparisons where precision is relevant.

To put this into perspective, 0.1 represents one-tenth, which is a larger fraction than one part of a thousand, while 0.01 represents one-hundredth, also larger than one part of a thousand. The whole number 1 represents a complete unit rather than a fraction. Therefore, the only value that correctly represents one part of a thousand is 0.001.