1
If January 1st, 2007, was a Monday, what day of the week will January 1st, 2008, be?
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Solution: Step 1: Identify the period: from January 1st, 2007, to January 1st, 2008.
Step 2: Determine if the year 2007 is an ordinary or leap year. Since 2007 is not divisible by 4, it is an ordinary year.
Step 3: Calculate the number of odd days. An ordinary year has 365 days, which means 1 odd day (365 mod 7 = 1).
Step 4: The day of the week for January 1st, 2008, will be 1 day beyond the day of the week for January 1st, 2007.
Step 5: Given that January 1st, 2007, was Monday.
Step 6: Counting forward 1 day from Monday gives Tuesday.
Step 7: Therefore, January 1st, 2008, will be a Tuesday.
4
Identify the two-digit number using the following statements: I. The sum of its digits is 7. II. The difference between the original number and the number with its digits interchanged is 9. III. The digit in the ten's place is greater than the digit in the unit's place by 1. Determine which combination of statements is sufficient.
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Solution: Step 1: Let the tens digit be 'x' and the units digit be 'y'. The original number is 10x + y. The number with digits interchanged is 10y + x.
Step 2: Analyze Statement I: 'Sum of the digits is 7.'
- x + y = 7. (Possible numbers: 16, 25, 34, 43, 52, 61, 70). Not sufficient alone.
Step 3: Analyze Statement II: 'Difference between the number and the number obtained by interchanging the digits is 9.'
- (10x + y) - (10y + x) = 9
- 9x - 9y = 9
- Dividing by 9: x - y = 1.
- (Possible numbers: 21, 32, 43, 54, 65, 76, 87, 98). Not sufficient alone.
Step 4: Analyze Statement III: 'Digit in the ten's place is bigger than the digit in the unit's place by 1.'
- This translates to x = y + 1, which is equivalent to x - y = 1.
- This statement alone is not sufficient as it is the same condition as Statement II.
Step 5: Evaluate combinations:
- Consider Statements I and II together (or I and III, as II and III are equivalent):
- x + y = 7
- x - y = 1
- Add these two equations: (x + y) + (x - y) = 7 + 1 => 2x = 8 => x = 4.
- Substitute x = 4 into x + y = 7: 4 + y = 7 => y = 3.
- This uniquely determines the number as 43.
Step 6: Conclusion: Both Statement I and Statement II (or Statement I and Statement III) are sufficient to determine the number. Since the given options for this problem are mutually exclusive and do not provide a clear 'Either/Or' choice for I+II and I+III, selecting 'None of these' means that a single specific answer option covering this specific situation is not available from the list, though a combination of statements does indeed solve the problem.
7
What can be determined about the number of pencils in a box given two statements: A. Subtracting four from the total yields a prime number. B. The total is a multiple of 3.
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Solution: ## Step 1: Understand Statement A
Statement A implies that if we subtract four from the total number of pencils, we get a prime number. This means the total number of pencils could be 6 (prime: 2), 7 (prime: 3), 9 (prime: 5), 11 (prime: 7), and so on.
## Step 2: Understand Statement B
Statement B says the total number of pencils is a multiple of 3. This means the total could be 3, 6, 9, 12, and so on.
## Step 3: Analyze Statement A Alone
From Statement A, possible totals include 6, 7, 9, 11, etc. It's clear that without more specific information, we cannot determine the exact number of pencils.
## Step 4: Analyze Statement B Alone
From Statement B, the total could be 3, 6, 9, etc. Again, without additional information, the exact number cannot be determined.
## Step 5: Combine Both Statements
Combining both, possible totals could still be 9, 15, 21, etc., as these satisfy both conditions (being a multiple of 3 and yielding a prime when 4 is subtracted).
## Step 6: Conclusion
Even with both statements, we cannot pinpoint the exact number of pencils in the box as there are multiple possibilities (9, 15, 21, etc.). Therefore, the question cannot be answered even after combining both statements.
8
Two individuals, X and Y, receive equal amounts of money. Determine the remaining amount with X based on given statements. Statement I: Y purchases an item using some of X's money, resulting in X having half of Y's remaining amount. Statement II: The shopkeeper returns $20 when Y pays with a $50 note.
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Solution: Step 1: Understand that both X and Y start with equal amounts of money, let's call it M.
Step 2: From Statement I, after Y buys an item and pays with X's money, X has M - (some amount) and Y has M + (some amount) - cost of item.
Step 3: It's given that X has half as much money as Y, so we can form an equation based on this relationship.
Step 4: Statement II provides that the cost of the item is $30 because Y paid $50 and got $20 back.
Step 5: Combining both statements, if the item costs $30 and X paid for it, we can calculate the exact amounts.
Step 6: Let's assume X gave Y $30 for the item. So, X has M - 30 and Y has M + 30 - 30 = M.
Step 7: According to Statement I, M - 30 = 0.5 * M, which implies M = 60.
Step 8: Therefore, X has 60 - 30 = $30 left.
Step 9: Both statements together allow us to determine the money left with X.
10
For the year 2007, determine the date of the last Saturday in May.
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Solution: Step 1: First, determine the day of the week for May 1st, 2007, using the calendar formula: (Date + Month Code + Last Two Digits of Year + Number of Leap Years + Century Code) / 7.
Step 2: Identify the values for May 1st, 2007:
* Date: 1
* Month Code (May): 2
* Last two digits of Year (2007): 7
* Number of Leap Years from 2000 to 2007: 1 (2004).
* Century Code (2000-2099): 6
Step 3: Sum these values: 1 + 2 + 7 + 1 + 6 = 17.
Step 4: Divide the sum by 7 and find the remainder: 17 mod 7 = 3.
Step 5: Map the remainder to the day of the week (assuming 0 = Saturday, 1 = Sunday, ..., 3 = Tuesday). So, May 1st, 2007, was a Tuesday.
Step 6: Find the first Saturday in May 2007. If May 1st is Tuesday:
* May 1 (Tuesday) + 4 days = May 5 (Saturday). So, May 5th is the first Saturday.
Step 7: List all Saturdays in May by adding 7 days:
* May 5th
* May 5th + 7 days = May 12th
* May 12th + 7 days = May 19th
* May 19th + 7 days = May 26th
* May 26th + 7 days = June 2nd (This falls outside May).
Step 8: Therefore, the last Saturday in May 2007 was May 26th.
16
Seven people - Pepper, Hulk, Ironman, Hawkeye, Thor, Loki, and Black Widow - are seated in a circular arrangement with equal distances between adjacent individuals. Given specific positional clues, who is seated immediately to the left of Black Widow?
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Solution: ## Step 1: Understand the given conditions
The individuals are seated in a circle with equal distances between them. Ironman is two places to the right of Loki, who is one place to the right of Hawkeye. Pepper forms a 90-degree angle with Thor and a 120-degree angle with Hulk. Hulk is opposite Black Widow and to the left of Thor.
## Step 2: Determine the position of Loki and Hawkeye
Given that Ironman is two places right of Loki and Loki is one place right of Hawkeye, we can deduce their sequence: Hawkeye, Loki, Ironman.
## Step 3: Position Pepper, Thor, and Hulk
Pepper forms a 90-degree angle with Thor and a 120-degree angle with Hulk. Given the circular nature and equal distances, Pepper must be at a position that creates these angles with Thor and Hulk.
## Step 4: Identify Hulk's and Black Widow's positions
Hulk is opposite Black Widow. Given the angles and positions, we can start piecing together the arrangement.
## Step 5: Finalize the seating arrangement
With Hulk opposite Black Widow and to the left of Thor, and considering the angles and positions of others, we deduce the seating order.
## Step 6: Determine who is to the immediate left of Black Widow
Based on the arrangement and given clues, Pepper Potts is the only person who can be seated on the immediate left of Black Widow.
The correct answer is Pepper Potts.
17
What is the birth year of a person? Given: 1. The person is 30 years younger than a relative. 2. The person's sibling, born in 1980, is 40 years younger than the same relative.
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Solution: Step 1: Analyze statement 1 - The person is 30 years younger than a relative.
Step 2: Analyze statement 2 - The person's sibling, born in 1980, is 40 years younger than the relative.
Step 3: Determine the relative's birth year using both statements.
Step 4: Calculate the person's birth year based on the relative's age and the sibling's birth year.
Step 5: From statement 2, if the sibling was born in 1980 and is 40 years younger than the relative, the relative was born in 1940.
Step 6: Since the person is 30 years younger than the relative born in 1940, the person was born in 1970.
Step 7: Therefore, both statements are required to find the person's birth year.
19
Determine the day of the week for June 20th, 1837.
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Solution: Step 1: Break down the target date (June 20th, 1837) into complete years and days within the target year. This means 1836 complete years + days from Jan 1, 1837, to June 20, 1837.
Step 2: Calculate odd days for 1836 years:
* Odd days in 1600 years (4 * 400) = 0 odd days.
* Remaining years = 1836 - 1600 = 236 years. Break this into 200 years + 36 years.
* Odd days in 200 years = 3 odd days.
* Odd days in 36 years: Number of leap years in 36 years = 9 (36/4=9). Number of ordinary years = 36 - 9 = 27.
* Total odd days in 36 years = (27 * 1) + (9 * 2) = 27 + 18 = 45 odd days. Reduce 45 mod 7 = 3 odd days.
* Total odd days for 1836 years = 0 (1600) + 3 (200) + 3 (36) = 6 odd days.
Step 3: Calculate odd days from January 1st, 1837, to June 20th, 1837:
* Year 1837 is not a leap year.
* January: 31 days = 3 odd days.
* February: 28 days = 0 odd days.
* March: 31 days = 3 odd days.
* April: 30 days = 2 odd days.
* May: 31 days = 3 odd days.
* June: 20 days = 6 odd days (20 mod 7 = 6).
* Total odd days for months = 3 + 0 + 3 + 2 + 3 + 6 = 17 odd days. Reduce 17 mod 7 = 3 odd days.
Step 4: Sum all odd days: 6 (from years) + 3 (from months) = 9 odd days.
Step 5: Reduce 9 mod 7 = 2 odd days.
Step 6: Map the total odd day to the day of the week (assuming 0 = Sunday, 1 = Monday, 2 = Tuesday, etc.).
Step 7: 2 odd days corresponds to Tuesday.
Step 8: Therefore, June 20th, 1837, was a Tuesday.