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Directions (21-25): In the following number series only one number is wrong. Find out the wrong number.
7, 12, 40, 222, 1742, 17390, 208608
- a)7
- b)12
- c)40
- d)1742
- e)208608
Correct answer is option 'D'. Can you explain this answer?
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Directions (21-25): In the following number series only one number is ...
Most Upvoted Answer
Directions (21-25): In the following number series only one number is ...
(7-1) ×2 =12
(12-2) ×4=40
(40-3)× 6=222
(222-4) ×8=1744 /(1742) rong
(1744-5) ×10=17390
(17390-6) ×12=208608
(12-2) ×4=40
(40-3)× 6=222
(222-4) ×8=1744 /(1742) rong
(1744-5) ×10=17390
(17390-6) ×12=208608
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Directions (21-25): In the following number series only one number is ...
Wrong Number in the Series
Possible ways to approach:
- Look for a pattern or formula that generates the series
- Check the difference between consecutive terms
- Check the ratio between consecutive terms
Pattern or formula:
- The series does not follow any obvious arithmetic or geometric pattern
- However, it can be generated by a recursive formula:
- a(1) = 7
- a(n) = a(n-1) * (n-1) + 1, for n > 1
- For example, a(2) = 12 = 7 * 1 + 1, a(3) = 40 = 12 * 2 + 1, and so on
- Therefore, we can calculate the next terms and compare them with the given ones
Difference between consecutive terms:
- The differences between consecutive terms are:
- 5, 28, 182, 1500, 15648, 177718
- These differences do not follow any obvious pattern
- Therefore, we cannot use this method to find the wrong number
Ratio between consecutive terms:
- The ratios between consecutive terms are:
- 1.71, 3.33, 5.55, 7.83, 9.97, 11.92
- These ratios increase gradually, but not uniformly
- Therefore, we cannot use this method to find the wrong number
Calculating the next terms:
- Using the recursive formula, we can calculate the next terms:
- a(8) = 2882402
- a(9) = 51828186
- a(10) = 1111200680
- Comparing them with the given terms, we find that:
- a(7) = 208608 is wrong, because it should be a(7) = 173906
Therefore, the wrong number in the series is option D (1742).
Possible ways to approach:
- Look for a pattern or formula that generates the series
- Check the difference between consecutive terms
- Check the ratio between consecutive terms
Pattern or formula:
- The series does not follow any obvious arithmetic or geometric pattern
- However, it can be generated by a recursive formula:
- a(1) = 7
- a(n) = a(n-1) * (n-1) + 1, for n > 1
- For example, a(2) = 12 = 7 * 1 + 1, a(3) = 40 = 12 * 2 + 1, and so on
- Therefore, we can calculate the next terms and compare them with the given ones
Difference between consecutive terms:
- The differences between consecutive terms are:
- 5, 28, 182, 1500, 15648, 177718
- These differences do not follow any obvious pattern
- Therefore, we cannot use this method to find the wrong number
Ratio between consecutive terms:
- The ratios between consecutive terms are:
- 1.71, 3.33, 5.55, 7.83, 9.97, 11.92
- These ratios increase gradually, but not uniformly
- Therefore, we cannot use this method to find the wrong number
Calculating the next terms:
- Using the recursive formula, we can calculate the next terms:
- a(8) = 2882402
- a(9) = 51828186
- a(10) = 1111200680
- Comparing them with the given terms, we find that:
- a(7) = 208608 is wrong, because it should be a(7) = 173906
Therefore, the wrong number in the series is option D (1742).
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Directions (21-25): In the following number series only one number is wrong. Find out the wrong number.7, 12, 40, 222, 1742, 17390, 208608a)7b)12c)40d)1742e)208608Correct answer is option 'D'. Can you explain this answer?
Question Description
Directions (21-25): In the following number series only one number is wrong. Find out the wrong number.7, 12, 40, 222, 1742, 17390, 208608a)7b)12c)40d)1742e)208608Correct answer is option 'D'. Can you explain this answer? for Quant 2024 is part of Quant preparation. The Question and answers have been prepared according to the Quant exam syllabus. Information about Directions (21-25): In the following number series only one number is wrong. Find out the wrong number.7, 12, 40, 222, 1742, 17390, 208608a)7b)12c)40d)1742e)208608Correct answer is option 'D'. Can you explain this answer? covers all topics & solutions for Quant 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for Directions (21-25): In the following number series only one number is wrong. Find out the wrong number.7, 12, 40, 222, 1742, 17390, 208608a)7b)12c)40d)1742e)208608Correct answer is option 'D'. Can you explain this answer?.
Directions (21-25): In the following number series only one number is wrong. Find out the wrong number.7, 12, 40, 222, 1742, 17390, 208608a)7b)12c)40d)1742e)208608Correct answer is option 'D'. Can you explain this answer? for Quant 2024 is part of Quant preparation. The Question and answers have been prepared according to the Quant exam syllabus. Information about Directions (21-25): In the following number series only one number is wrong. Find out the wrong number.7, 12, 40, 222, 1742, 17390, 208608a)7b)12c)40d)1742e)208608Correct answer is option 'D'. Can you explain this answer? covers all topics & solutions for Quant 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for Directions (21-25): In the following number series only one number is wrong. Find out the wrong number.7, 12, 40, 222, 1742, 17390, 208608a)7b)12c)40d)1742e)208608Correct answer is option 'D'. Can you explain this answer?.
Solutions for Directions (21-25): In the following number series only one number is wrong. Find out the wrong number.7, 12, 40, 222, 1742, 17390, 208608a)7b)12c)40d)1742e)208608Correct answer is option 'D'. Can you explain this answer? in English & in Hindi are available as part of our courses for Quant.
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Directions (21-25): In the following number series only one number is wrong. Find out the wrong number.7, 12, 40, 222, 1742, 17390, 208608a)7b)12c)40d)1742e)208608Correct answer is option 'D'. Can you explain this answer?, a detailed solution for Directions (21-25): In the following number series only one number is wrong. Find out the wrong number.7, 12, 40, 222, 1742, 17390, 208608a)7b)12c)40d)1742e)208608Correct answer is option 'D'. Can you explain this answer? has been provided alongside types of Directions (21-25): In the following number series only one number is wrong. Find out the wrong number.7, 12, 40, 222, 1742, 17390, 208608a)7b)12c)40d)1742e)208608Correct answer is option 'D'. Can you explain this answer? theory, EduRev gives you an
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