Question 1015644
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A=gross for singer A; B=gross for singer B=A-$23 million
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You add the two, not multiply:
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A+B=$413 million . Substitute (A-$23 million) for B.
A+(A-$23 million)=$413 million . Add $23 million to each side.
2A=$436 million . Divide each side by 2.
A=$218 million 
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ANSWER 1: Tour A grossed $218 million
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B=A-$23 million=$218-$23 million=$185 million
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ANSWER 2: Tour B grossed $195 million
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CHECK:
A+B=$413 million
$218 million + $195 million = $413 million
$413 million = $413 million
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