Question 698970
mr.santos treated his students to a movie for winning the state contest. this also required taking some of the students parents as chaperones. the movie theater charges 4 dollars for each student and 6 dollars for each adult. if mr.santos spent 180 dollars on movie tickets and took 40 people( including himself ), how many students and how many adults went to see the movie? 
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People equation: a + s = 40
Value equation::6a +4s = 180
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Simplify:
a = -s+40
a = (-2/3)s + 30
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Substitute:
-s+40 = (-2/3)s+30
(1/3)s = 10
s = 30
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a = -s+40 = 10
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Elimination:
3a + 3s = 3*40
3a + 2s = 90
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Subtract and solve for "s":
s = 120-90 = 30
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3a + 2s = 90
3a + 60 = 90
3a = 30
a = 10
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Cheers,
Stan H.
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