Piano Tuners Estimate

Estimate the number of piano tuners in Chicago, assuming:

1. Chicago has a population of about 3 million people.
2. A family has four members on the average.
3. One in every five families owns a piano.
4. A piano tuner takes a two-week vacation during the year.
5. A piano tuner services four pianos every day of the work week on the average.
6. All pianos are tuned once a year on the average.

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