Know the answer but not how to get it...

Aurora Borealis

I suspect maybe I'm being a bit slow, which seeing my eyes are stinging from staring at a computer screen is highly probable....

So the answer is apparently 95 anyway... Can you explain how that is arrived at?

I would be eternally grateful...

The average length of unemployment for every person of working age in France is 170 days, but the figure is 220 days for unemployed people aged 45 and over. Of the 30 million working population in France in 2005, 18 million were aged 45 and over. What was the average length of unemployment in France for the working population aged under 45 in 2005?

LeixlipRed

30 million multiplied by 170 gives you the total number of days spent unemployed which is 5.1 bn. Then subtract the 18 million by 220 days that makes up the over 45s to leave you with 1.14bn unemployed days for under 45s and divide by 12 million to get the average which is 95 as you said

Thomas_S_Hunterson

Solve for x:
170 = (18/30) * 220 + (12/30) * x

Aurora Borealis

Thank you so much!

Aurora Borealis

Do you know how to solve this one...

Some tourists return to the same country several times in the same year. In 2000, it was noted that in Italy 80% of tourists made a single trip to the country, 15% came twice, and 5% at least 3 times. How many individual tourists visited Italy in 2000?

hivizman

This is one of those questions where you have to make some assumptions. First, what constitutes a "trip"? The statistical table is headed "tourists staying at least one night when visiting a country", so it will not include people who make a day trip to Italy. For example, someone on holiday on the French Riviera can get on a train and visit the Ligurian Riviera in Italy, returning to France in the evening.

So let's assume that a "trip" includes an overnight stay.

Secondly, does the table count "tourists" or "trips"? In other words, if a tourist visits Italy more than once in a year, is that tourist counted separately each time he or she visits, or only once? If the latter, then the number of trips in 2000 was simply 22,800,000, as shown in the table. But this isn't interesting as a question (and would be much more difficult to count than simply the number of tourist visits), so it makes sense to assume that each visit is counted separately in the table.

Take a random group of 100 visitors to Italy. Then 80 of these (80%) visited only once (making 80 visits), 15 of these visited twice (making 30 visits), and 5 of these visited at least three times. For convenience, assume that the remaining 5 each visited exactly three times - this will slightly underestimate the number of visits - giving a further 15 visits. So the total number of visits made by 100 visitors on average will be 80 + 30 + 15 = 125 trips.

Hence, if the total number of trips was 22,800,000 in 2000, the total number of individual visitors was 22,800,000 x (100/125) = 18,240,000.

Aurora Borealis

Thanks for that hivizman and that's exactly how I worked it out too but the rather baffling optional answers are;

• Up to 20 330 000
• Up to 21 500 000
• Up to 21 670 000
• Up to 22 800 000
• Up to 20 220 000

None of which I can figure out..

hivizman

The only number that I can see as making sense is the 22,800,000 figure we are given in the table. None of the other four numbers gives a straightforward ratio when divided by 22,800,000. Ideally, in a multiple choice question, all the answers must be at least plausible, but I can't link the information given in the question with the options provided (except for 22,800,000, which, if the expected answer, would make the question trivial).

Any ideas, anyone?

Turtwig

I'm not 100% confident on this, but if you take a sample of 100 visitors to Italy.

5 people will visit three times : 15 visits.
15 people will visit twice, but this already includes the 5 people who visit 3 times so 10 people will visit twice only : 20 visits.
80 people will visit once, but this already includes the people who visit twice and 3 times. So 80 -(5+10) =65 will visit once only : 65 visits.

Giving you a 100 visits in total. So, if the total trip no of trips is 22,800,000, the total number of visitors is 22,800,000 x100/100 = 22,800,000. Which does seem a bit counter intuitive.

hivizman

Malty_T wrote: »

I'm not 100% confident on this, but if you take a sample of 100 visitors to Italy.

5 people will visit three times : 15 visits.
15 people will visit twice, but this already includes the 5 people who visit 3 times so 10 people will visit twice only : 20 visits.
80 people will visit once, but this already includes the people who visit twice and 3 times. So 80 -(5+10) =65 will visit once only : 65 visits.

Giving you a 100 visits in total. So, if the total trip no of trips is 22,800,000, the total number of visitors is 22,800,000 x100/100 = 22,800,000. Which does seem a bit counter intuitive.

But then you have accounted for only 80 people out of your sample of 100. What about the other 20 people? They can't include any of the five who visit at least three times, any of the 10 (on your numbers) who visit twice, or any of the 65 (on your numbers) who visit once only. So none of these 20 visitors can have visited Italy at all. However, they must have visited at least once, or they would not count as "visitors to Italy". So your argument leads to a contradiction.

LeixlipRed

OP, what's this for? It could just be a mistake I suppose.

Predalien

Don't like dragging up old threads but it looks to me if you take the people who go once as 80%, the 15% who go twice as 7.5%, and the 5% who go 3 or more times as 1.67% for a total of approx 89.17%, then you get the first answer of 20.33m as the total number of individual visitors, you sort of have to ignore anyone who went more than 3 times.