Solution:

Part 1: Calculate Anna's weekly earnings for $2400 in sales

Anna's total earnings for a week consist of her base salary plus her commission.

1. Base salary: $450 per week (guaranteed salary)
2. Commission rate: $15\% = 0.15$
3. Sales amount: $2400

The commission Anna earns on $2400 of sales is: $\text{Commission} = \text{Sales} \times \text{Commission Rate} = 2400 \times 0.15 = 360$

Her total earnings are: $\text{Total Earnings} = \text{Base Salary} + \text{Commission} = 450 + 360 = 810$

Thus, Anna makes $810 in a week with $2400 in sales.

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Part 2: General formula for Anna's weekly earnings

If Anna makes $x$ dollars in sales, her earnings can be calculated as: $\text{Total Earnings} = 450 + (x \times 0.15)$

You can use this formula to compute her earnings for any given sales amount $x$.

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Final Answer:

• For $2400 in sales: Anna makes $810 in a week.
• For $x$ dollars in sales: Anna makes $450 + (x \times 0.15)$.

Would you like me to graph her earnings for varying sales values or explain any step in detail?

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Related Questions:

1. What would Anna's total earnings be if her sales were $5000?
2. What percentage of her total earnings would come from her commission if she sold $2400 worth of clothing?
3. How much sales would Anna need to make to earn a total of $1000 in a week?
4. What is Anna's weekly income if she makes no sales at all?
5. If the commission rate changed to 20%, how would her earnings be affected?

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Tip:

Using a general formula like $\text{Earnings} = 450 + (x \times 0.15)$ allows you to solve similar problems quickly by substituting $x$ with the sales amount.