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Opens on Chapter 17’s example: Inez’s 2 1/4 cups of flour for 6, cooked for 15.
A fixed part plus a rate
Inverse: more people, less time
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From the book, Chapter 17. 2 1/4 cups for 6 is 3/8 cup each, so 5 5/8 cups for 15 (× 2 1/2). Rice at 3 cups for 8 is 7 1/2 cups for 20. A taxi at $3 plus $2 a mile: 5 miles $13, 10 miles $23, not $26. Four people taking 6 hours is 24 person-hours: three take 8 hours, six take 4. At $1.09 a euro, €45 is $49.05.
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