To determine which number comes first when the numbers are listed from least to greatest, let's convert each of them into decimal form for easier comparison:

1. One sixth:
   $\frac{1}{6} \approx 0.1667$

2. Negative 2:
   This is already a decimal number: $-2.0$

3. Square root of 7 ($\sqrt{7}$):
   $\sqrt{7} \approx 2.6458$

4. Negative nine halves ($-\frac{9}{2}$):
   $-\frac{9}{2} = -4.5$

5. 1.1:
   This is already a decimal number: $1.1$

Now, let's list these numbers with their approximate decimal forms:

• One sixth: $0.1667$
• Negative 2: $-2.0$
• $\sqrt{7}$: $2.6458$
• Negative nine halves: $-4.5$
• 1.1: $1.1$

Finding the Smallest Number

The smallest (most negative) number in the list is negative nine halves ($-4.5$).

Listing the Numbers in Order

Now, we arrange all the numbers from least to greatest:

1. $-\frac{9}{2}$ (or $-4.5$)
2. $-2$
3. $\frac{1}{6}$ (or approximately $0.1667$)
4. $1.1$
5. $\sqrt{7}$ (or approximately $2.6458$)

Answer

The number that comes first when the numbers are listed from least to greatest is negative nine halves ($-\frac{9}{2}$).

Would you like more details or have any questions about this problem?

Here are 5 related questions for practice:

1. How do you compare fractions with decimals directly?
2. What is the decimal equivalent of $\frac{2}{5}$?
3. Which is greater: $0.75$ or $\frac{3}{4}$?
4. What is the square root of $5$ approximately?
5. If given three numbers $-3$, $0.5$, and $\sqrt{10}$, which is the greatest?

Tip: Always convert different forms (fractions, square roots) into decimals to compare them easily.