Question 72840
Let x= the amount of sales and y= money earned in a week.
cellular phone sales: y=150+0.2x
stereo sales: y=200+0.1x
A- To earn the same amount of money at both jobs, how much will you need to sell in a week?
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cell earnings = stereo earnings:
150+0.2x = 200+0.1x
0.1x=50
x=$500 in sales
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B- After talking with salespeople, you estimate weekly sales of about $600 with either job. At which job will you earn more money? 
cell earnings = 150+0.2*600
cell earnings = $270
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stereo earnings = 200+0.1(600)
stereo earnings = $260
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Cheers,
Stan H.