Chapter 2: Functions, Graphs, and Lines
110 + 0.37(t − 250) = 190 0.37t = 190 + 92.5 − 110 = 172.5 172.5 t= ≈ 466.22 0.37
65 + 0.41(t − 100) = 110 0.41t = 110 + 41 − 65 = 86 t=
ISM: Introductory Mathematical Analysis
86 ≈ 209.76 0.41
Thus, plan P2 is better for t between 83.14 and 209.76 minutes.
Thus, plan P3 is better for t between 209.76 and 466.22 minutes.
3. P3 and P4 intersect at the point where P3 = 110 + 0.37(t − 250) and P4 = 190. This occurs when
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