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Bunuel
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In year x, it rained on 40% of all Mondays and 20% of all Tuesdays. On 29 Sep 2021, 01:00
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51% (01:27) correct 49% (01:30) wrong based on 501 sessions

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In year x, it rained on 40% of all Mondays and 20% of all Tuesdays. On what percentage of all the weekdays in year x did it NOT rain?

(1) During year x, it rained on 10% of all Wednesdays.

(2) During year x, it did not rain on 70% of Thursdays and it did not rain on 95% of all Fridays.
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E
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Bunuel
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In year x, it rained on 40% of all Mondays and 20% of all Tuesdays. On 02 Oct 2021, 01:30
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Bunuel
In year x, it rained on 40% of all Mondays and 20% of all Tuesdays. On what percentage of all the weekdays in year x did it NOT rain?

(1) During year x, it rained on 10% of all Wednesdays.

(2) During year x, it did not rain on 70% of Thursdays and it did not rain on 95% of all Fridays.
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Manhattan Prep Official Explanation

In order to answer the question, we must know the annual rain percentages for each weekday and the proportion each weekday represents relative to the total number of weekdays in year x. (Since we don't know the specific day that year x starts, we cannot assume that Mondays represent exactly 1/5 of the total weekdays in year x, Tuesdays represent 1/5 of the total weekdays in year x, etc.)

(1) INSUFFICIENT: This provides information about the percentage of Wednesday that it rained but this ALONE is not sufficient.

(2) INSUFFICIENT: This provides information about the the percentage of Thursdays and the percentage of Fridays that it rained, but this ALONE is not sufficient.

(1) AND (2) INSUFFICIENT:  Both statements together, in conjunction with the information given in the question, provide the annual rain percentages for each weekday during year x. However, because we do not know the proportion each weekday represents relative to the total number of weekdays in year x, we still do not have sufficient information to answer the question.

The correct answer is E.
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In year x, it rained on 40% of all Mondays and 20% of all Tuesdays. On 03 Nov 2021, 07:12
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Bunuel
In year x, it rained on 40% of all Mondays and 20% of all Tuesdays. On what percentage of all the weekdays in year x did it NOT rain?

(1) During year x, it rained on 10% of all Wednesdays.

(2) During year x, it did not rain on 70% of Thursdays and it did not rain on 95% of all Fridays.
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This question is a part of Are You Up For the Challenge: 700 Level Questions collection.
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In year x, it rained on 40% of all Mondays and 20% of all Tuesdays. On 01 Sep 2022, 09:12
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I have a question. If you have 52 weeks in a year, then you will have 52 mondays, 52 tuesdays, etc.

I dont understand this:

In order to answer the question, we must know the annual rain percentages for each weekday and the proportion each weekday represents relative to the total number of weekdays in year x. (Since we don't know the specific day that year x starts, we cannot assume that Mondays represent exactly 1/5 of the total weekdays in year x, Tuesdays represent 1/5 of the total weekdays in year x, etc.)
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In year x, it rained on 40% of all Mondays and 20% of all Tuesdays. On 20 Sep 2022, 06:07
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valeriacastro11
I have a question. If you have 52 weeks in a year, then you will have 52 mondays, 52 tuesdays, etc.

I dont understand this:

In order to answer the question, we must know the annual rain percentages for each weekday and the proportion each weekday represents relative to the total number of weekdays in year x. (Since we don't know the specific day that year x starts, we cannot assume that Mondays represent exactly 1/5 of the total weekdays in year x, Tuesdays represent 1/5 of the total weekdays in year x, etc.)
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We have 365 days in a year resulting in 52,142... weeks. The number 52 is rounded and an over simplification which can not be used for solving this problem here.
Take this example:
The first day of the year in 2022 was Saturday and the Last day of year is Wednesday. Resulting in # of Saturdays = 53
The first day of the year in 2021 was Friday and the Last day of year is Friday. Resulting in # of Saturdays = 52

We clearly see that based on the starting weekday of each year the number of certain weekdays shifts.
Hope that explains it :)
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In year x, it rained on 40% of all Mondays and 20% of all Tuesdays. On 29 Apr 2023, 11:27
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Bunuel
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In year x, it rained on 40% of all Mondays and 20% of all Tuesdays. On what percentage of all the weekdays in year x did it NOT rain?

(1) During year x, it rained on 10% of all Wednesdays.

(2) During year x, it did not rain on 70% of Thursdays and it did not rain on 95% of all Fridays.


Manhattan Prep Official Explanation

In order to answer the question, we must know the annual rain percentages for each weekday and the proportion each weekday represents relative to the total number of weekdays in year x. (Since we don't know the specific day that year x starts, we cannot assume that Mondays represent exactly 1/5 of the total weekdays in year x, Tuesdays represent 1/5 of the total weekdays in year x, etc.)

(1) INSUFFICIENT: This provides information about the percentage of Wednesday that it rained but this ALONE is not sufficient.

(2) INSUFFICIENT: This provides information about the the percentage of Thursdays and the percentage of Fridays that it rained, but this ALONE is not sufficient.

(1) AND (2) INSUFFICIENT:  Both statements together, in conjunction with the information given in the question, provide the annual rain percentages for each weekday during year x. However, because we do not know the proportion each weekday represents relative to the total number of weekdays in year x, we still do not have sufficient information to answer the question.

The correct answer is E.
Show more

Hello, I do not understand the explanation by Manhattan Prep. It's year X, and the question does not specify a leap year or not. For the sake of simplicity, can we not assume 52 times each weekday (given 52 weeks in 1 year)? Accordingly we can take percentages, that is - Total rainy days = 40% of M + 20% of T + 10% of W + 30% of Thurs + 5% of F. Would that be invalid? I was thinking the right answer should be C instead.
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In year x, it rained on 40% of all Mondays and 20% of all Tuesdays. On 19 Jun 2024, 11:05
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Hello Bunuel

In this question is it possible to just use the percentages and average out the possibilities had we had the split for the number of days.
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In year x, it rained on 40% of all Mondays and 20% of all Tuesdays. On 26 Oct 2025, 12:48
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What have we decided? Is it okay to assume 52 of each week day a year?
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