PT7.S4.Q19 - it takes 365.25 days

Accounts Playable

Hey guys, I added the other LR section to my PT this week, and I came across this question. It was a complete confidence error, and I felt pretty strong about the answer I picked. In other words, I don't see how A isn't correct nor how B is correct.

Breakdown of stimulus: Since our calendar system is stupid, certain important holidays don't fall on the same day of the week each year. If the last day of the year and the extra day added at the end of the year every 4 years didn't belong to a week, some of these scheduling problems could be fixed.

What I am looking for: We need an answer choice that shows that a scheduling problem would still exist.

Answer A: What's wrong with this? If you anniversary falls on the day that doesn't have a week or on the last day of the year (12/31), doesn't that create a problem during the years with an extra day? Would the extra day be 12/32 or still considered 12/31?

Answer B: I don't see how this would be a problem. Just don't work every 7th day. How does the new schedule create a problem here?

Answer C: So what? They just have to attend a certain number of days of school.

Answer So what? This is completely fixed, I think since holidays will be on the same day every year.

Answer E: Why can't you plan ahead with the new schedule?

Cant Get Right

Yeah, this one is tough. I remember making the same error and it took me a long time before it made sense. It’s an odd question. I mean, I guess it’s still logic, but it really requires thinking through the proposal and its implications. To some extent, we need to do this always, but this question kind of takes it a step further.

I think with answer choice A, the primary issue is that the question stem specifies “continued scheduling conflicts.” So, at worst, this only makes birthdays weird. It doesn’t create any ongoing problem though, so because of the specific wording of the question we’ve got to eliminate it.

So with B, this is where you’ve really got to think about how executing the idea in the stim would work. So it seems kind of complicated, but at the same time it makes sense. It’s kind of a hassle that holidays always fall on a different day of the week. So doing this, while a little weird, would result in a more consistent calendar. Great, right?

Well, let’s consider the folks in answer choice B. So we normally think about this group with the day of rest falling on either Saturday or Sunday, depending on the religion we’re talking about. So what the proposal does is it throws off the traditional day of rest (Saturday or Sunday) from the every seven days routine. With the new calendar, we’ve got one or two days that aren’t days. That’s complicated enough, probably easiest just to make those holidays, what a mess. So on a leap year, we go from Friday then, three days later, Saturday. So if your religious observance is based on every seventh day (Saturday, let’s say), what happens next week? Your day of rest is going to fall on Thursday for the rest of the year now. And next year, it’s going to be on a Wednesday. And the next year it’ll be on a Tuesday. So obviously, the work week currently accommodates the day of rest thing, but now we’ve got a problem. And if you have a job and you’re observing every seventh day as a day of rest, your calendar is chaos.

runiggyrun

The stimulus is suggesting keeping the "leap year", but making the leap day a "no day of the week - let's call it Whateversday", and also making Dec 31 a "Whateversday".
They don't say where they'd put the leap day, but it won't create any extra problems that current leap days don't. Under the current system, if your birthday is on Feb 29, you'd have a birthday every four years, sometimes on Monday, sometimes on Tuesday, etc. Under the new system, it would be every four years on Whateversday.
If your birthday is on Dec 31'st, you'd have a birthday every year, on Whateversday. None of these would be extra problems compared to the current system, so A is incorrect.
Now, let's say you're religious and you take every 7th day off. Under the current system, you can take every Sunday off, and that coincides with the day most employers plan to have people off.
Let's say we implement the changes in 2017.
You take every Sunday off, starting with Sunday, Jan 1st and ending with Dec 24th. You also take Dec 31st off, as it's 7 days from Dec 24th (this is supposed to be a Sunday under the current calendar, but it would be a Whateversday under the new one). No problems for 2017. Your next day off would be Jan 7th, which should have been a Sunday. However, because 2018 now starts with Sunday, Jan 1st, instead of Monday Jan 1st (the whole point of the change is that Jan 1st will from now on always be a Sunday, Jan 2nd always a Monday and so on), your day off Jan 7th now falls on a Saturday. Next year your day off will be Jan 06, which will be a Friday, the year after it will be Jan 05, which will be a Thursday. So, people who take every 7th day off will be taking a different weekday off every year under the new system, which might be a problem for employers.

extramedium

Bump. Can someone break this down for me in very very VERY simplified terms? I've never understood the leap year concept, and I really hate moving on from questions that I do not understand. Can someone please help me?

All I currently understand is that the author is suggesting eliminating the last day of every year and eliminating the leap year, making it 364 days, 52 weeks, and 7 days every week. So to my knowledge, each date would be on the same day of the week every year, and I don't understand how that presents a conflict for anyone. The seventh day of the week would be on the same day every year, no?

Clemens_

PT7.S4.Q19 – Calendar Changes

This miscellaneous question discusses a proposed calendar change and asks us to identify a population for which this change would be problematic.

The stimulus starts with the observation that each revolution of the earth around the sun (= each year) takes 365.25 days, i.e. 52 weeks and 1.25 days. This raises the question how these 1.25 extra days are supposed to fit into the year / month / week structure of the calendar system. Traditionally, this problem has been approached through the addition of an extra day every four years – that is, .25 of the 1.25 extra days have been allowed to accumulate until they form 1.00 days (0.25x4=1.00). What happens to the remaining 1.00 extra day per year in this traditional system is not addressed and remains an open question.

After describing this traditional approach to the calendar, the author points out that this approach creates ‘many scheduling problems,’ in particular in relation to anniversaries: Under the present system, it is not the case that e.g. one's birthday is on the same day of the week each year. Instead, birthdays get assigned different days of the week in different years.

The author seeks to resolve these scheduling problems by introducing a new calendar type. The idea is: Instead of letting the .25 left over days per year accumulate over a four year time span until they form a new weekday, we make four of these .25 leftover days a new day that occurs every fourth year but that does not also belong to any week. That is, we keep the idea of adding an extra day to our years every fourth year, but we only include this extra day into the year system, not into the week system. The same idea is supposed to apply to the 1.00 extra day that we presently incorporate both into the year and into the week system. We thus would get a disruption of the weekly system (under the new proposal, it would no longer be the case that each day that is part of a year would also be a part of a week), but we would get a more neatly organized yearly system of keeping track of time that would avoid the scheduling problems that the author dislikes.

The two calendar systems thus differ from another as follows:

(1) Traditional approach: We break up the 365.25 days that make up each year into 52 weeks and one additional day (= 52x7+1). In addition to that, we are using a leap year system that lets the remaining .25 days / year accumulate over a four year time span such that every fourth year gets an additional day (.25x4=1). Each individual day furthermore serves as a weekday (Monday, Tuesday etc.), such that it is not the case that every year e.g. starts with a Monday and ends on a Sunday. Instead, our seven day sequences of weekdays (Monday, Tuesday etc.) imperfectly align with the ways in which we split up our years: Rather than having each year e.g. start with a Monday and end with a Sunday, years can also start and end with different days of the week.

(2) Proposed new approach: We keep the leap year approach of adding extra days to our years, but we don’t also add these extra days into our weekly system. Each week goes from Monday to Sunday, each year comprises 52 weeks, and the additional 1.25 days just serve as extras that stand beside the Monday-Friday system. Each year can thus e.g. start on a Monday and end on a Sunday; the left-over days remain non-components of any week.

So, whom would this disadvantage? It seems that the people most affected by this would be people who rely on the Monday-Friday weekly calendar system, as opposed to the monthly or yearly calendar system: At present, these people can use existing calendars to keep track of time, because at present each day that makes up a given year also is a day that makes up part of a week. Under the new system, however, the weekly and yearly calendar systems would be disassociated from another, such that it would no longer be the case that every day is both a part of a year and a part of a week.

(A) People whose birthday is on Dec 30 or 31. Would they be disadvantaged? Probably not, they don’t rely on the weekly system of keeping track on time. According to the stimulus, these people might even get an advantage from the proposed calendar change; their birthdays here would happen on the same day of the week every year. So this group does not seem disadvantaged.
(B) People who rely on the 7-day weekly system for religious reasons. Yes, these people would be disadvantaged by the proposed calendar change. They don’t need the 1.25 extra days per year to fit neatly into the yearly system. Instead, they focus on the seven day sequences that make up individual weeks, and this system is precisely what the author proposes to disrupt. This is the right answer; these people need every day to be a part of a week!
(C) People who focus on the total number of days per year. This population would seem to remain unaffected by the proposed calendar change; the total number of days per year would remain the same.
(D) Employed people who get three day breaks from work if holidays fall on a Monday or Friday. This population might get affected. To ascertain this, however, we would have to assess the specific holidays that come up in the calendar, as well as the days on which they presently tend to fall. Do these holidays presently have a tendency to fall on Mondays or Fridays? We have no idea; the stimulus does not provide us with this information. This thus seems to be an answer choice we just cannot assess.
(E) People who plan events several years in advance. This population again would seem unaffected; long-term planning would seem possible in both calendar systems.

Takeaways: I don’t know a good automatism to get this question resolved in time; it does seem to rely a lot on intuition. The key information to keep track of is that the author proposes to make the yearly system more organized by breaking up the weekly system, such that it would no longer be the case that each day is both a part of a week and a part of a year. That is, part to whole reasoning is involved, but in a non-standard way. Process of elimination likely is the way to go; (B) is the only answer choice that mentions the weekly system. The fact that the author proposes to make some days parts of no week suggests that this must be the right answer, as this proposal obstructs weekdays-based systems of keeping track of time. Flag this question under timed conditions and then get back to it; a detailed reflection on this question only makes sense in review.