To round a number to the nearest thousandth, follow these steps:

1. Locate the thousandth place: The third digit to the right of the decimal point is the thousandth place.
2. Check the digit in the next place (ten-thousandth): The fourth digit to the right of the decimal point determines whether to round up or keep the thousandth place as is.
   • If the ten-thousandth digit is 5 or greater, round up the thousandth place by 1.
   • If the ten-thousandth digit is less than 5, keep the thousandth place as it is and drop all digits beyond it.
3. Rewrite the number: Include all digits up to the thousandth place.

Example:

• Round $3.14159$ to the nearest thousandth:
  1. The thousandth place is 1.
  2. The ten-thousandth place is 5 (greater than or equal to 5).
  3. Round up: $3.14159 \to 3.142$.

If you have a specific number to round, please provide it!

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Do you want more examples or have questions?

5 Related Questions:

1. How do you round to the nearest hundredth?
2. What is the difference between truncating and rounding?
3. Can you explain rounding to significant figures?
4. How does rounding affect precision in scientific calculations?
5. How do you apply rounding rules for negative numbers?

Tip:

When rounding decimals, always double-check the digit you're rounding based on the context, especially in mathematical proofs or financial calculations!