To place the numbers in order on a number line, we first identify their approximate positions:
- -13.1 (a negative number, far to the left)
- -2.99 (still negative, but closer to zero)
- 0.199 (just above zero)
- 5.6 (a positive number, more than 5)
- 6 ½ (which is 6.5, just a little more than 6)
Now, arranging them in increasing order, we have:
-13.1, -2.99, 0.199, 5.6, 6.5 (or 6 ½)