Answer:
There are 225 adult tickets.
Explanation:
Let the number of adult tickets but represented by A while the number of student tickets be represented by S.
We are told the total is 391, so A+S=391.
There are 59 fewer student tickets (S) sold than adult tickets (T).
So there are 59 more adult tickets which means, A=59+S.
We are going to solve the system:
A+S=391
A=59+S
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We are going to input the second equation into the first:
A+S=391 with A=59+S
(59+S)+S=391
59+S+S=391
59+2S=391
Subtract 59 on both sides:
2S=391-59
2S=332
Divide both sides by 2:
S=332/2
S=166
So A=59+S given S=166 means A=59+166=225.
There are 225 adult tickets while there is 166 student tickets.