Answer:
Step-by-step explanation:
<h3>a)</h3>
8 adult tickets cost 8($9.50) = $76
21 kids tickets cost 21($3) = $63
The total cost of these tickets is $76 +63 = $139.
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<h3>b)</h3>
aa adult tickets cost 9.50aa
kk kids tickets cost 3.00kk
The total cost of these tickets is 9.50aa +3.00kk.
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<em>Additional comment</em>
We ordinarily expect a variable to be a single letter. This problem statement defines each variable using a double letter, so that is what we have used. (Sometimes Brainly doubles up variable content in copied text, so we suspect that may have happened here.)