Question 1034181
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    The Family Fine Arts Center charges $21 per adult and $12 per senior citizen for its performances. On a recent weekend evening when 486 people paid admission, the total receipts were $6894. How many who paid were senior citizens?

    a. 208 senior citizens
    b. 368 senior citizens
    c. 118 senior citizens
    d. 278 senior citizens
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<U>Answer</U>.  Option b. 368 senior citizens.


<U>Solution</U>. 


<pre>
Let s be the number of seniors.

Then the number of adults is (486-s).

The value function is f(x) = 12*s + 21*(486-s) dollars.

Only s = 368 gives the value of $6894.

To find the answer, you actually do not need to solve the equation.
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