Final answer:
Mrs. Larson's son washed more of the laundry since he washed 7/21 while Mrs. Larson washed 6/21 of the laundry. After combining their portions, 8/21 of the laundry still needs to be washed.
Step-by-step explanation:
To determine who washed most of the laundry, we need to compare the fractions that represent the portions of laundry washed by Mrs. Larson and her son. Mrs. Larson washed 2/7 of the laundry while her son washed 1/3 of it.
To compare them, it's easiest if we have a common denominator. The smallest common denominator between 7 and 3 is 21. Converting each fraction to have a denominator of 21, we get:
- Mrs. Larson's portion: 2/7 = 6/21
- Her son's portion: 1/3 = 7/21
Comparing 6/21 and 7/21, we see that 7/21 is greater, which means her son washed more of the laundry.
To find out how much of the laundry still needs to be washed, we add the two portions together and subtract from the whole (1 or 21/21):
Total washed: 6/21 + 7/21 = 13/21
Laundry remaining: 21/21 - 13/21 = 8/21
Therefore, 8/21 of the laundry still needs to be washed.