Let's analyze Marissa's steps and identify any errors:
-
Write each decimal as a fraction:
- 1.4 = 14/10 = 7/5
- 0.2 = 2/10 = 1/5
So, the values are:
- Negative one-sixth = -1/6
- Negative one-third = -1/3
- 1.4 = 7/5
- 0.2 = 1/5
- Two-thirds = 2/3
Her conversion of decimals to fractions is not mentioned in the original problem. Assuming she converts them correctly, we move to the next step.
-
Write every fraction with a common denominator of 18:
- -1/6 = -3/18
- -1/3 = -6/18
- 7/5 = 50.4/36 (incorrect, should be calculated)
- 1/5 = 3.6/18 (incorrect, should be calculated)
- 2/3 = 12/18
Common denominator need's to be verified.
After conversion, we have:
- -1/6 = -3/18
- -1/3 = -6/18
- 7/5 = (7*18)/5 = 126/30
- 1/5 = (1*18)/5= 36/30
- 2/3 = 12/18
-
Plot the numbers on the number line.
- If correctly plotted after converting to a common denominator like 18, the point of placement should have been noted and accurately plotted. This would require care in estimating placement.
-
List the numbers from left to right as they are plotted on the number line.
- The ordering should be from least to greatest using the correctly plotted values.
Errors identified:
- Marissa should have only plotted the correct fractions as calculated after step 2.
- Marissa should have used a common denominator of 18 if plotting accurately the values based on 1.5 as she mentions this value should be (compound decimal).
- Listing numbers from right to left is incorrect; they should always be labeled from left to right in standard practice from least to greatest.
In summary:
- Need proper calculation of decimal conversions.
- She should have used a common denominator of 18 instead of incorrectly checking as 30.
- She should plot after conversion accurately and not list from right to left but rather from left to right.
None of the specific error statements provided completely encapsulate her steps, but her intent needs framing properly around correct values and plotting strategy given fractions from least to greatest.