Suggest how you would work out the thickness of a single sheet of paper if the only measuring device available was a ruler and its smallest division was 1 mm. ​

Explanation:

Stack a bunch of papers together in a neat pile. If you’re able to, use a freshly unwrapped stack of papers. Since they are all the same size, you will be able to get a more accurate measurement. If you don’t already have a stack, choose papers that appear to be roughly the same size. Stack them on top of a flat surface, such as a table.[1]

You can still take the measurement if your stack has different types of paper mixed in, but the result won’t be as accurate as it normally would. Each sheet could be a different thickness.

If you have to measure a specific, single sheet of paper, use a digital caliper instead for the most accurate result.

Count the number of papers in the stack. If you’re using fresh paper, check the wrapping. Manufacturers typically list the number of sheets there. Otherwise, count each paper individually and write the number down for later.[2]

Check the manufacturer’s count carefully. Sometimes they count double-sided sheets twice. If that happens, divide the total count by 2 to get the actual number of papers in the stack.

For example, 500 double-sided pages / 2 = 250 sheets. Measure the thickness of the entire stack with a ruler. Set a ruler against the edge of the stack. Press it down firmly against the table. Then, take the measurement and record it. The measurement should be the same on all sides of the stack, so it doesn’t matter which one you choose.[3]

For uneven stacks, such as newspaper, consider placing something heavy on top of it to keep it pinned down. Otherwise, you might have a hard time getting a precise reading