Hi could someone help me how to solve this problem?

Thanks

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# How to estimate the number of visitors per year in the Eiffel tower?

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Hmm, the daily airport working hours * landing time is the N° of incoming flights daily in one parking spot. There might be many parking spots/gates in one airport.
I have a question regarding this point "THEREFORE, % of tourists visiting Tour Eiffel in one day = 100 / 4 = 25%". Let's say that we are talking about March 19th, and tourist stay 4 days like you say. So 25% of those arriving on March 16 will go on the 4th day, 25% of those arriving on March 17th will go on their 3rd day, regarding March 18th arrivals 25% of them will go the following day, and then 25% of those arriving on the 19th will visit on the same day. So in the end shouldn't it be 100% of the daily tourist visiting the Eiffel Tower? Thank you for your thought process, enjoyed it a lot
Hi Andrea, thanks for sharing your framework! I find quite usefull to approach this problem by using number of tourist incoming through airport, but in my opinion there are a few issues which led to underestimation of actual number of incoming tourists. First of all, we need to be aware of the fact, that large airports like the one in Paris have a number of runways which are in use - therefore there are much more than 42 incoming flights per airport. I would simply multiply your number by number of runways per large airport - maybe 4 would be a reasonable number. At he same time, we should think there might be a number of people visiting paris by train or bus from neigbouring countries, as well as some French visiting the the tower, so I would add about 20% to number of people arriving by plane. Last but not least, I agree with Jorge, I don't think we should devide the number of tourist arriving daily by the lenght of their stay. In case I plug my suggestion to your formulas (e.g. multiply number of tourist coming by plane by 4, add 20% for people coming by other means of transportation and don't take into consideration the lenght of stay, we would get a number of 7 milion. Too proof my assumpitons, I checked the actual number online - there were 6.9 milion visitors in 2016.
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Hi could someone help me how to solve this problem?

Thanks

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Hi, hope it helps.

I will address the problem this way:

- N° of tourists daily * % of them visiting Tour Eiffel * 365

- N° of tourists daily = n° of incoming flights * % of tourists each flight * N° of passengers each flight * n° of airports

- N° of incoming flights daily = daily airport working hours * landing time

- N° of passengers each flight = 0,75 * full capacity (my assumption)

- % of tourists visiting Tour Eiffel in one day = 100% / avg vacation period

- landing time is about 20 min per flight

- daily airport working hours is 14H (from 7 am to midnight)

- THEREFORE N° of incoming flights daily = 14h * 60 min / 20 min = 42 incoming flights

- N° of airports = 3 (CDG, BEAU, ORL)

- N° of passengers each flight = 0,75 * 150 = 120 passengers

- % of tourists each flight = 50% (my assumption to make the count easier)

- THEREFORE, N° of tourists daily = 42 * 3 * 0,5 * 120 = 7560 (round to 7500)

- Avg vacation period = 4 days

- THEREFORE, % of tourists visiting Tour Eiffel in one day = 100 / 4 = 25%

- FINALLY, N° VISITORS PER YEAR TOUR EIFFEL = 360 (easy to calculate) * 0,25 * 7500 = 675.000

I welcome any comment, suggestion and fruitful critic.

Andrea

3 comments

Ning

on Sep 25, 2017
Jorge

on Oct 13, 2017
Maros

on Oct 22, 2017
I'd start by figuring the number of access points to Eiffel tower, I think you have three elevators and a stairs.

After that, I'd divide the year in peak days and non-peak days. Peak days will be the months of April through September and the rest are non- peak.

I would figure out the operating hours of the tower, i assume from about 9 AM till 12 AM. I would estimate the number of round trips each lift does during an hour (60 minutes divided by the duration of the lift's trip in minutes). Would then estimate the capacity of the lift, and during peak days, i think it is fair to assume almost full capacity throughout the day.

So i'd get the number of visitors for every lift trip and multiply it by the number of trips per day to get the number of visitors per lift per day. I would then ,multiply this by the number of days per year and then multiply it by 3 because we have three lifts.

For non-peak day i'd assume hald the amount of visitors as a quick rough estimation.

When it comes to the stairs, i would estimate the number of visitors that enter the stairs per minute ( probably 4 individuals per minute during peak times). I would follow the same approach as above to get the total per peak days. I would also divide this number by 2 for non-peak times.

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