write a ratio in 3 ways, comparing the first quantity to the second. A week has 5 school days and 2 weekends. Second question about 1 in 4 people swims at least 6 times each year.

To write a ratio comparing the first quantity to the second, we can use the format "first quantity : second quantity". Here are three ways to write the ratios for the given situations:

1. Ratio of school days to weekends:
- 5 school days : 2 weekends
- This ratio represents the number of school days relative to the number of weekends.

2. Ratio of weekdays to weekends:
- 5 weekdays : 2 weekends
- Since weekends consist of both Saturday and Sunday, this ratio represents the number of weekdays relative to the number of weekends.

3. Ratio of school days to total days:
- 5 school days : 7 total days
- This ratio represents the number of school days relative to all the days in a week, including both school days and weekends.

Moving on to the second question:

To write a ratio when 1 in 4 people swims at least 6 times each year, we can use the format "number of people who swim at least 6 times : total number of people". Here's how we can represent this ratio:

Ratio of people who swim at least 6 times to the total number of people:
- 1 person : 4 people
- This ratio represents the number of people who swim at least 6 times each year relative to the total number of people.