Question

Assume the population of a large city like New York City is about 4 × 10^6 people, with about 1.97 people per household. Approximately 1 household in 16.1 has a piano. The piano keyboard has about 64 notes (8 octaves) with about 2 strings per note. A piano should be tuned once per year (365.25 days). A piano tuner can tune about 3 pianos per day. And, finally, pianos tuners work 250 days per year. How many pianos tuners are there in New York City?

Answer 1

So here are the given information:

4 x 10^6 people 

1.97 people = 1 household 

16.1 households = 1 piano 

1 piano = 1 tuning/year 

1 tuner = 3 tunings/working day 

1 year = 250  working days 


Multiplying everything: 

4 x 10^6 people x (1 household/1.97 people) x (1 piano/16.1 households) = 126115.33 pianos in NYC 

126115.33 pianos x (1 (tuning/year)/1 piano) x (1 year/250 working days) x (1 working day/3 pianos/tuner) = 168.15 tuners 


Therefore about 168 piano tuners in NYC.