Natalie earns $2.50 for each CD she sells and $3.50 for each DVD she sells. Natalie sold 45 DVDs last year. She earned a total of $780 last year selling CDs and DVDs.

Question

Natalie earns $2.50 for each CD she sells and $3.50 for each DVD she sells.  Natalie sold 45 DVDs last year.  She earned a total of $780 last year selling CDs and DVDs.  
Write an equation that can be used to determine the number of CDs (c) Natalie sold last year.  How many CDs did Natalie sell last year?  Show all work.

Natalie claims that she can earn more money this year by selling only 1/3 the number of CDs that she sold last year and by tripling the amount of DVDs she sold last year.  Is Natalie's claim correct?  Use words, numbers, and/or symbols to support your answer.

PsyDAG · Accepted Answer

2.50CD + 3.50(45) = 780 Divide CDs by 3 and multiply DVDs by 3 at above prices to calculate earnings. 2.50CD/3 + 3.50(45)(3) = ?