difficult problem solving quesiotn !

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by abhasjha » Sun Nov 17, 2013 10:47 am
problems on calendar till now has not been a part of GMAT exam . just for the sake of knowledge the answer is Thursday ..

June 25, 1982 - friday
June 25, 1983 - Saturday ( the same date next year to fall on a day ahead of previous year)
June 25, 1984 - Monday ( 1 more day added for leap year so instead of sunday it becomes monday)
June 25, 1985- Tuesday
June 25,1986- wednesday
June 25,1987- Thursday

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by Brent@GMATPrepNow » Sun Nov 17, 2013 10:56 am
aalradadi wrote:June 25, 1982, fell on a friday. On which day of the week did June 25, 1987, fall? (note: 1984 was a leap year.)

SUNDAY
MONDAY
TUESDAY
WEDNESDAY
THURSDAY
I agree with abhasjha.

This would ever be an actual GMAT question, because it relies on facts concerning leap years that not everyone knows about. The fact of the matter is that most people believe that leap years occur every 4 years, but this is not the case. There are exceptions, and if you don't know the exceptions (or you have a misunderstanding of the exceptions), you'll answer the question incorrectly.

The GMAT typically doesn't ask questions that require knowledge of obscure facts.

For more, see https://en.wikipedia.org/wiki/Leap_year

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by Mathsbuddy » Sun Nov 17, 2013 11:32 am
1982 to 1987 = 5 years, including 1 leap year:

4 * 365 + 1 * 366 = 1826 days

1826/7 = 260 weeks Remainder 6 days

Friday + 6 days = Thursday

Answer = Thursday

I certainly believe there was sufficient information in the question to answer this. (Everyone should know that there are 365 days in a year and 366 in a leap year. If not, it's easy to work out if you know February changes from 28 to 29 days on a leap year.) However it was more an arithmetic problem than a logical problem.

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by aalradadi » Sun Nov 17, 2013 11:37 am
but i got it form the official gmat prep!
would they put questions that will not be part of the real test?

and thanks for your replies guys :)

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by Brent@GMATPrepNow » Sun Nov 17, 2013 12:05 pm
Fair enough. The question still feels un-GMAT-like to me.

Typically, if the GMAT test-makers wanted to create a question like this, they wouldn't assume that test-takers have the requisite information. Instead, they'd provide whatever information was needed.

If this is an official GMAT question, I suspect that it appeared 2 or 3 decades ago, when most test-takers were from the US and Canada. Today, the GMAT test-makers strive to avoid any cultural bias (for more, see https://www.gmac.com/why-gmac/gmac-news/ ... -bias.aspx). Since this question hinges one's familiarity with the term "leap year," it might not be fair to students whose first language is not English.

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by [email protected] » Sun Nov 17, 2013 2:54 pm
Hi aalradadi,

While I agree with the concerns about this question, it IS essentially just a "remainder" question.

Each year (except for the Leap Year) is 365 days. Since there are 7 days/week....

1 year = 365 days = 52 weeks + 1 day

So, there's one extra day per year (and the Leap Year has 2 extra days). Each extra day "pushes" the date one day forward in the calendar.

So, in 1983, June 25 was on a Saturday
In 1984, June 25 was on a Monday (because of the Leap Year)
In 1985, June 25 was on a Tuesday
In 1986, June 25 was on a Wednesday
In 1987, June 25 was on a Thursday

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by GMATGuruNY » Sun Nov 17, 2013 3:06 pm
aalradadi wrote:June 25, 1982, fell on a friday. On which day of the week did June 25, 1987, fall? (note: 1984 was a leap year.)

SUNDAY
MONDAY
TUESDAY
WEDNESDAY
THURSDAY
Alternate approach:

Between 1982 and 1987 are 4 non-leap years and 1 leap year.
Each non-leap year is composed of 365 days; a leap year is composed of 366 days.
Thus, from June 25, 1982 to June 25, 1987, the total number of days = 4(365) + 366.

Since June 25, 1982 is a Friday, every passing of 7 days will yield another Friday.
364 is a multiple of 7.
Rephrase the total number of days in terms of 364:
4(365) + 366

= 4(364+1) + (364+2)

= (4*364 + 4) + (364+2)

= 5(364) + 6

= (multiple of 7) + 6

= Friday + 6 days

= Thursday.

The correct answer is E.
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