Answer :
As per linear equation, the number of people who bought ticket in advance is 2800.
What is a linear equation?
"A linear equation is an equation in which the highest power of the variable is always 1."
Given, the number of people is 4000.
70% of the people bought ticket in advance.
Therefore, the number of people who bought ticket in advance is
[tex]= \frac{4000(70)}{100}\\ = 2800[/tex]
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