A point is chosen randomly on PS. Identify the probability that the point is not on QR.
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PS has length 3 + 13 + 8 = 24. QR has length 13, so the probability that the point falls on QR is [tex]\dfrac{13}{24}[/tex], and so the probability that it doesn't is [tex]1-\dfrac{13}{24}=\dfrac{11}{24}[/tex].