Answer:
![\begin{gathered} 5.1234\approx5.123 \\ 6.6666\approx6.667 \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/nrbz2rg76kvfsec8hdzxy97wcmuo6tghug.png)
Step-by-step explanation:
We want to round up the given number to the nearest thousandths.
![5.1234](https://img.qammunity.org/2023/formulas/mathematics/college/12c4jfs26kneivjrjaqa48a4u9p1n97cyb.png)
To the nearest thousandth which is also to 3 decimal place, we have;
![\approx5.123](https://img.qammunity.org/2023/formulas/mathematics/college/k100ocqnc8vxpnyzkufxaxahjk4grtd23v.png)
Also;
![6.6666](https://img.qammunity.org/2023/formulas/mathematics/college/njgrrkpsv56r8xmzu4vmvu5yktcfjefxhy.png)
To the nearest thousandth, we have;
![6.667](https://img.qammunity.org/2023/formulas/mathematics/college/1fzsem5kqzd8loqjoctbw53cazrssf01b3.png)
Note that numbers from 5 above will be rounded up, while numbers below 5 will be rounded down.