Answer:
325 adult tickets
Step-by-step explanation:
This "sum and difference" problem can be solved by assigning a single variable to the quantity you want to know. Let 'a' represent the number of adult tickets sold. Then (a-60) is the number of student tickets sold, and the total number sold is ...
a +(a -60) = 590
2a = 590 +60
a = 650/2 = 325
There were 325 adult tickets sold.
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<em>Check</em>
325-60 = 265 student tickets were sold, for a total of 325+265 = 590.
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<em>Additional comment</em>
You may have noticed that the larger number of tickets (number of adult tickets) was found to be the average of the two numbers given in the problem statement. That will generally be the case for a "sum and difference" problem.
