Answer :
Sadie's earnings varys directly with the number of hours worked.
The number of hours worked in a week where her earnings would be $210 is 20 hours.
What is direct variation?
Direct variation is when two variables move in the same direction. If one variable increases, the other variable increases. Sadie's earnings increase with hours worked. This is a direct variation.
How many hours would be worked when earnings is 210?
Hours worked = Total earnings / earning per hour
210 / 10.50 = 20 hours
To learn more about direct proportion, please check: https://brainly.com/question/27233899
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