She should book 8 clients each day to maximize profit
The quadratic function is given as:
[tex]P = -15x^2 + 240x - 640[/tex]
Differentiate the function
[tex]P' = -30x + 240[/tex]
Set the function to 0
[tex]-30x + 240 = 0[/tex]
Collect like terms
[tex]30x = 240[/tex]
Divide through by 30
[tex]x = 8[/tex]
Hence, she should book 8 clients each day to maximize profit
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