Using proportions, it is found that:
- In an 8-hour day, she keys 48 pages.
- For a day, her gross earnings are of $72.
- For a week, her gross earnings are of 72 x 7 = $504.
<h3>Proportions:</h3>
This question is solved using the proportions given, which are:
- Payment of $1.50 per page of 30 lines.
- Retha keys 6 pages per hour.
Hence, in an 8-hour day, she keys 6 x 8 = 48 pages.
Since she earns $1.50 per page, for a day, her gross earnings are of 48 x 1.5 = $72.
Considering a week has 7 days, for a week, her gross earnings are of 72 x 7 = $504.
To learn more about proportions, you can take a look at brainly.com/question/24372153