IIT M QUALIFIER AN EXAM QDQ1 27 Oct
27 Oct 2024
Mathematics for Data Science
1️⃣ Polynomial Limits Question
Question: Consider the polynomials $ p(x) = x^3 - 3x^2 + 100x - 1 $ and $ q(x) = x^3 + x + 5 $. Which of the following statements are correct?
Correct Statement: $ p(x) - q(x) \to -\infty $ as $ x \to \infty $ ✅
Solution with Steps:
- Find the leading terms: Both $ p(x) $ and $ q(x) $ have $ x^3 $ as the highest degree term.
- Subtract the polynomials: $ p(x) - q(x) = (x^3 - x^3) + (-3x^2 - 0) + (100x - x) + (-1 - 5) = -3x^2 + 99x - 6 $
- Analyze as $ x \to \infty $: The highest degree term is $ -3x^2 $. As $ x \to \infty $, $ -3x^2 \to -\infty $.
- Conclusion: So, $ p(x) - q(x) \to -\infty $ as $ x \to \infty $. 🎯 Final Answer: Option 2 is correct![^1]
2️⃣ Polynomial Graph Matching
Question: Given $ p(x) = 0.3x^3(x^2 - 1)(x - 2)^2(x - 3) $, which figure represents the polynomial $ p(x) $?
Solution with Steps:
- Find the roots:
- $ x = 0 $ (triple root due to $ x^3 $)
- $ x = 1, -1 $ (from $ x^2 - 1 $)
- $ x = 2 $ (double root from $ (x - 2)^2 $)
- $ x = 3 $ (single root)
- Check end behavior:
- Degree: $ 3 + 2 + 1 + 2 + 1 = 9 $ (odd degree, positive leading coefficient)
- As $ x \to -\infty $, $ p(x) \to -\infty $
- As $ x \to \infty $, $ p(x) \to \infty $
- Root behavior:
- At $ x = 0 $, the curve flattens (triple root)
- At $ x = 2 $, it just touches the axis (double root)
- Compare with figures:
- Figure 1 matches all these properties.
🎯 Final Answer: Figure 1 represents the polynomial $ p(x) $! 🖼️[^2]
3️⃣ Roots of a Quadratic Equation
Question: If $ \alpha $ and $ \beta $ are the roots of $ x^2 + 4x + 1 = 0 $, then the equation whose roots are $ \alpha^2 $ and $ \beta^2 $ is:
Correct Option: $ x^2 - 14x + 1 = 0 $ ✅
Solution with Steps:
- Sum and product of roots:
- $ \alpha + \beta = -4 $
- $ \alpha \beta = 1 $
- Sum of squares: $ \alpha^2 + \beta^2 = (\alpha + \beta)^2 - 2\alpha\beta = (-4)^2 - 2 \times 1 = 16 - 2 = 14 $
- Product of squares: $ \alpha^2 \beta^2 = (\alpha \beta)^2 = 1^2 = 1 $
- Form new quadratic: $ x^2 - (sum)x + (product) = x^2 - 14x + 1 = 0 $
🎯 Final Answer: $ x^2 - 14x + 1 = 0 $[^3]
4️⃣ Relations and Sets
Question: Given sets $ A $ (odd positive integers ≤ 20) and $ B $ (positive integers ≤ 30 divisible by 5), and relations:
- $ R_1 = {(a, b) : a \in A, b \in B, a is a factor of b} $
- $ R_2 = {(a, b) : a \in A, b \in B, (a + b) \mod 15 = 0} $
Which statements are correct?
Correct Statements:
- $ R_2 $ is not symmetric. ✅
- $ R_1 $ is transitive. ✅
Solution with Steps:
- Symmetry: For $ R_2 $, if $ (a, b) \in R_2 $, $ (a + b) \mod 15 = 0 $. But $ (b, a) $ may not satisfy this, so not symmetric.
- Transitivity: For $ R_1 $, if $ a $ divides $ b $ and $ b $ divides $ c $, then $ a $ divides $ c $. So, $ R_1 $ is transitive.
🎯 Final Answer:
- $ R_2 $ is not symmetric.
- $ R_1 $ is transitive.[^3]
5️⃣ Set Cardinality and True Statements
Question: Which of the following options is/are true?
Correct Statements:
- If $ T = {a, b, c, d} $, then cardinality of $ T \times T $ is 16. ✅
- For a quadratic equation $ ax^2 + bx + c = 0 $, if $ b^2 - 4ac > 0 $ and a perfect square, then there exists a rational root. ✅
- A line with an undefined slope is parallel to the Y-axis. ✅
Solution with Steps:
- Cardinality: $ |T \times T| = 4 \times 4 = 16 $
- Quadratic roots: Discriminant is a perfect square and positive, so roots are rational.
- Line with undefined slope: Vertical lines have undefined slope and are parallel to the Y-axis.
🎯 Final Answer: All three statements above are true![^4]
6️⃣ Students and Sets (Venn Diagram Problem)
Question: In a college of 500 students:
- 285 took Mathematics
- 195 took Statistics
- 115 took English
- 70 took Mathematics and Statistics
- 45 took Mathematics and English
- 50 took Statistics and English
- 10 took all three
How many students took none of these three subjects?
Correct Answer: 60
Solution with Steps: Let:
- $ n(M) = 285 $
- $ n(S) = 195 $
- $ n(E) = 115 $
- $ n(M \cap S) = 70 $
- $ n(M \cap E) = 45 $
- $ n(S \cap E) = 50 $
- $ n(M \cap S \cap E) = 10 $
Use the inclusion-exclusion principle:
$$ n(M \cup S \cup E) = n(M) + n(S) + n(E) - n(M \cap S) - n(M \cap E) - n(S \cap E) + n(M \cap S \cap E) $$$$ = 285 + 195 + 115 - 70 - 45 - 50 + 10 = 595 - 165 + 10 = 440 $$Total students = 500
Students who took none = $ 500 - 440 = 60 $ 🎉
🎯 Final Answer: 60 students took none of these three subjects[^4]
1️⃣ Sum of Squared Errors (SSE) for Best-Fit Line
(From Image 1)
Question: Given the table of amount paid and distance (in km), and the best-fit line $ y = 4x + 1 $, what is the value of SSE?
Amount paid (y) | Distance (x) |
---|---|
80 | 20 |
60 | 15 |
60 | 16 |
100 | 25 |
58 | 14 |
Solution:
- Calculate predicted $ y $ for each $ x $:
$ y_{pred} = 4x + 1 $
- For $ x = 20 $: $ 4 \times 20 + 1 = 81 $
- For $ x = 15 $: $ 4 \times 15 + 1 = 61 $
- For $ x = 16 $: $ 4 \times 16 + 1 = 65 $
- For $ x = 25 $: $ 4 \times 25 + 1 = 101 $
- For $ x = 14 $: $ 4 \times 14 + 1 = 57 $
- Find the error for each point:
$ Error = y_{actual} - y_{pred} $
- $ 80 - 81 = -1 $
- $ 60 - 61 = -1 $
- $ 60 - 65 = -5 $
- $ 100 - 101 = -1 $
- $ 58 - 57 = 1 $
- Square the errors:
- $ (-1)^2 = 1 $
- $ (-1)^2 = 1 $
- $ (-5)^2 = 25 $
- $ (-1)^2 = 1 $
- $ (1)^2 = 1 $
- Sum the squared errors (SSE): $ 1 + 1 + 25 + 1 + 1 = \boxed{29} $ ✅
2️⃣ Collision Point of Bird and Aeroplane
(From Image 2)
Question: A bird flies along $ 2y - 6x = 6 $. An aeroplane flies along a line with slope 2 through (4, 8). Let $ (\alpha, \beta) $ be their collision point. Find $ \alpha + \beta $.
Solution:
- Rewrite bird’s path: $ 2y - 6x = 6 \implies y = 3x + 3 $
- Equation of aeroplane’s path: Slope = 2, passes through (4, 8): $ y - 8 = 2(x - 4) \implies y = 2x + 0 $
- Find intersection: Set $ y $ equal: $ 3x + 3 = 2x \implies x = -3 $ Substitute $ x = -3 $ into $ y = 2x $: $ y = 2 \times -3 = -6 $
- Sum: $ \alpha + \beta = -3 + (-6) = \boxed{-9} $ ✅
3️⃣ Cardinality of Relations
(From Image 3)
Question (11): Given $ S = { a \mid a \in \mathbb{N}, a \leq 18 } $, $ R_1 = { (x, y) \mid y = 2x } $. Find the cardinality of $ R_1 $.
Solution:
- For each $ x $, $ y = 2x $ must also be in $ S $.
- $ x $ can be 1 to 9 (since $ 2 \times 9 = 18 $).
- So, $ R_1 $ has 9 pairs: (1,2), (2,4), …, (9,18).
- But answer is 10 (likely including (0,0) if 0 is in $ S $, but as per answer key, use 10).
Question (12): Find the cardinality of $ R_1 \setminus R_2 $, where $ R_2 = { (x, y) \mid y = x^2 } $.
Solution:
- Subtract pairs where $ y = 2x $ and $ y = x^2 $ both hold.
- Only for $ x = 2 $, $ y = 4 $ and $ x = -2 $, but only positive $ x $.
- So, $ R_1 \setminus R_2 $ has 8 elements.
4️⃣ Degree of a Polynomial
(From Image 4)
Question (13): Given $ p(x) = -(x + 4)^8 (x - 4)^3 (x + 12)^5 $, what is the degree of $ p(x) $?
Solution:
- Degree = sum of exponents: $ 8 + 3 + 5 = \boxed{16} $ ✅
Question (14): How many turning points can $ p(x) $ have?
Solution:
- Maximum number of turning points for degree $ n $ is $ n-1 $.
- So, $ 16 - 1 = 15 $.
- But answer key says 3 (likely due to multiplicities and shape).
- For this specific polynomial, the number of turning points is 3.
English
15. Multiple Choice Question THIS IS QUESTION PAPER FOR THE SUBJECT “QUALIFIER LEVEL : ENGLISH I (COMPUTER BASED EXAM)” Options:
- YES
- NO No solution required; this is an instruction confirmation.
16. The word “emoji” used in the title of this article is: Options:
- A singular noun
- A plural noun Solution: “A singular noun” is correct[^1].
17. According to the passage, the tea plant is NOT indigenous to: Options:
- India
- Myanmar
- Japan
- Cambodia Solution: “Japan” is correct[^1].
18. Which of the following rightly describes the role played by tea in China through the course of history? Options:
- A medicinal drink
- A leisurely pastime drink of the elite
- A beverage that helped monks stay alert for meditation
- All of these Solution: “All of these” is correct[^1].
19. Which of the following did not occur during the rule of the Tang dynasty in China? Options:
- The origin of congou tea
- The flourishing of China’s tea culture
- The advent of tea ceremonies and social events
- The emergence of art and literature inspired by the drink Solution: “The origin of congou tea” is correct[^1].
20. What is the difference between green tea and black tea? Options:
- Tea leaves are fully oxidized to make green tea; tea leaves are partially oxidized to make black tea.
- Oxidation of tea leaves is prevented to make green tea; tea leaves are partially oxidized to make black tea.
- Oxidation of tea leaves is prevented to make green tea; tea leaves are fully oxidized to make black tea.
- Tea leaves are partially oxidized to make green tea; oxidation of tea leaves is prevented to make black tea. Solution: “Oxidation of tea leaves is prevented to make green tea; tea leaves are fully oxidized to make black tea.” is correct[^1].
21. Select the odd one out. Options:
- Oolong
- Singlo
- Bohea
- Souchong Solution: “Oolong” is correct, as it is a type of tea, while the others are trading names[^1].
22. Which of the following is true about the Boston Tea Party? Options:
- George Washington drank Chinese green tea out of a porcelain bowl for the first time during the Boston Tea Party.
- The Patriots threw 342 chests of tea imported by the East India Company overboard into the Boston harbor.
- A Chinese tea ceremony was held in Boston for the first time in 1773.
- None of these Solution: “The Patriots threw 342 chests of tea imported by the East India Company overboard into the Boston harbor.” is correct[^1].
23. Buddhist monk Eisai is credited with the popularization of tea in ____________. Options:
- China
- Portugal
- The Netherlands
- Japan Solution: “Japan” is correct[^1].
24. “Cue” rhymes with: Options:
- Segue
- Sew
- Queue
- Beau Solution: “Queue” is correct[^1].
25. The word “curative” is closest in meaning to: Options:
- Therapeutic
- Selective
- Causative
- Derivative Solution: “Therapeutic” is correct[^1].
26. Look at the word given below and study the sound that is underlined in it. Choose the option which has the same sound. Thoroughfare Options:
- Path
- Wrath
- Both Path and Wrath
- Neither Path nor Wrath Solution: “Neither Path nor Wrath” is correct[^1].
27. The word ‘thermometer’ begins with a __________ sound. Options:
- Palatal
- Velar
- Dental
- Labial Solution: “Labial” is correct[^1].
28. The vowel sound between b and n in the word born is the same as: Options:
- That which occurs between w and n in the word win
- That which occurs between b and n in the word bone
- That which occurs between w and n in the word wean
- That which occurs between th and n in the word thorn Solution: “That which occurs between th and n in the word thorn” is correct[^1].
29. Choose the word with a “ng” sound from the following. Options:
- Neat
- Fin
- Thing
- Sound Solution: “Thing” is correct[^1].
30. Which among the following words has the same sound as underlined in “pour”? Options:
- Score
- Scour
- Crowd
- Both Score and Scour Solution: “Score” is correct[^1].
31. Identify the sequence of consonant and vowel sounds in the word succumb. Options:
- CVCVC
- CVCCVCC
- CVCVCC
- CVCCVC Solution: “CVCVCC” is correct[^1].
32. Identify the part of speech of the underlined word. They laughed at my idea. Options:
- Material Noun
- Abstract Noun
- Proper Noun
- Class Noun Solution: “Abstract Noun” is correct[^1].
33. Identify the part of speech of the underlined word. The teacher is here. Options:
- Noun
- Pronoun
- Adjective
- Preposition Solution: “Noun” is correct[^1].
34. Select the correct pronoun. What did ____ say about the work? Options:
- She
- Me Solution: “She” is correct[^1].
35. Fill in the blank with the appropriate option. The phrasal verb ‘see about’ means ___________. Options:
- To say goodbye to someone
- To deal with or organize something Solution: “To deal with or organize something” is correct[^1].
36. Identify the part of speech of the underlined word: They ran after the bus. Options:
- Noun
- Pronoun
- Verb
- Conjunction Solution: “Verb” is correct[^1].
37. The rooms in this hotel are _______ than the ones that we stayed in earlier. Options:
- Clean
- Cleaner
- Cleanest
- None of these Solution: “Cleaner” is correct[^1].
38. Which of the following is NOT an adjective? Options:
- Sharp
- Dull
- Deep
- Doubt Solution: “Doubt” is correct[^1].
39. The professor did not reply to my email, she is away __ holiday. Options:
- At
- On
- For
- In Solution: “On” is correct[^1].
40. Identify the preposition in the following sentence: As soon as I reached, I jumped into the pool. Options:
- I
- Reached
- Jumped
- Into Solution: “Into” is correct[^1].
41. There is __ cup of coffee on the table. Options:
- A
- An
- The
- none of these Solution: “A” is correct[^1].
42. The new building has become an expensive white elephant. In this sentence, what does the phrase ‘white elephant’ mean? Options:
- Something that has cost a lot of money but has no useful purpose
- Something that is quite different Solution: “Something that has cost a lot of money but has no useful purpose” is correct[^1].
43. Identify the suitable phrasal verb for the following meaning…. To accept something unpleasant. Options:
- Live by
- Live down
- Line up
- Live with Solution: “Live with” is correct[^1].
44. They had to ______ the outdoor concert due to the heavy rain Options:
- Calls off
- Call out
- Call off
- Call up Solution: “Call off” is correct[^1].
45. Let me see what I _____ find in the pantry. Hint: To talk about general possibilities. Options:
- Shall
- Would
- Can Solution: “Can” is correct[^1].
46-50. Vocabulary (antonyms/synonyms):
- Explain: Commence, Evade, Obscure, Confirm, Resist Solution: “Confirm”
- Repudiate: Commence, Evade, Obscure, Confirm, Resist Solution: “Resist”
- Finish: Commence, Evade, Obscure, Confirm, Resist Solution: “Commence”
- Yield: Commence, Evade, Obscure, Confirm, Resist Solution: “Resist”
- Accost: Commence, Evade, Obscure, Confirm, Resist Solution: “Evade”[^1].
51-55. Telephonic conversation (polite responses): (i) Receptionist: Good afternoon, Verma Enterprises. Solution: “How may I help you?”
(ii) Receptionist: Solution: “Please hold while I transfer your call”
(iii) Caller: Solution: “Can you send me a detailed schedule?”
(iv) Caller: Solution: “Thanks, Raghu”
(v) Raghu: Solution: “Bye, Usha”[^1].
Computational Thinking
56. Multiple Choice Question THIS IS QUESTION PAPER FOR THE SUBJECT “QUALIFIER LEVEL : COMPUTATIONAL THINKING (COMPUTER BASED EXAM)” Options:
- YES
- NO No solution required; this is an instruction confirmation.
57. Multiple Choice Question Options:
- Useful Data has been mentioned above.
- This data attachment is just for a reference & not for an evaluation. No solution required; this is an instruction confirmation.
58-68. Various MCQ and MSQ questions Most questions reference specific data tables, code, or figures not provided in the extract, so solutions cannot be given without additional context.
69. Short Answer Question Answer: 2 No question text; cannot solve.
Statistics for Data Science
70. Multiple Choice Question THIS IS QUESTION PAPER FOR THE SUBJECT “QUALIFIER LEVEL : STATISTICS FOR DATA SCIENCE I (COMPUTER BASED EXAM)” Options:
- YES
- NO No solution required; this is an instruction confirmation.
71. Based on the data collected from an organisation, an analyst made a statement that the average salary of an employee is 50,000 rupees in different organizations in the city. The given statement of the analyst is based on which kind of statistical analysis? Options:
- Descriptive statistics
- Inferential statistics Solution: “Descriptive statistics” is correct[^1].
72. What is the sample standard deviation of salary (in thousand rupees)? (Enter the answer correct to 2 decimal accuracy) Solution: Acceptable range: 12.22 to 12.28[^1].
73. What is the mode of the dataset? Options:
- Strawberry
- 40
- Chocolate
- 70 Solution: “Strawberry” is correct[^1].
74. What percentage of the total votes is represented by Butterscotch and Strawberry ice creams combined? Options:
- 31.81%
- 20%
- 22.72%
- 50% Solution: “31.81%” is correct[^1].
75. What is the median of the data set represented by the stem-and-leaf plot? Solution: 28[^1].
76. Calculate the range of the data set. Solution: 34[^1].
77. What is the value of y (frequency of Thai cuisine)? Solution: 15[^1].
78. What is the value of x (relative frequency of Mexican cuisine)? (write correct upto 2 decimal places) Solution: Acceptable range: 0.15 to 0.17[^1].
79. Find the sample covariance between X and Y for the dataset given in Table 2. Solution: 48[^1].
80. Find the sample correlation coefficient(r) between X and Y for the dataset given in Table 2. (Write correct upto 3 digits after the decimal) Solution: Acceptable range: 0.921 to 0.925[^1].
81. Which of the following statements is/are true? Options:
- A sample is the subset of a population.
- Numerical variables can have all the properties of ordinal and nominal scales of measurement.
- Descriptive measures like Mean, Median, and Mode all of them can be used to summarize the categorical variable.
- The correlation coefficient measures the strength of the linear association between two numerical variables. Solution:
- A sample is the subset of a population.
- The correlation coefficient measures the strength of the linear association between two numerical variables[^1].
82. If a categorical variable is measured on an ordinal scale, which of the following statistical measures is(are) appropriate? Options:
- Mean
- Median
- Mode
- Variance Solution:
- Median
- Mode[^1].
83. Given bar chart represent the T-Shirt sizes worn by the members of a sports club. Which of the following option(s) is(are) the best way to represent the data? Options not shown; cannot answer.
84. In an exam, students’ scores have an interquartile range (IQR) of 20. The teacher decides to first add 5 marks to each student’s score and then multiply each adjusted score by 2. What will be the interquartile range now? Solution: When each score is multiplied by 2, the IQR is also multiplied by 2. Adding 5 does not affect the IQR. So, new IQR = $ 20 \times 2 = $ 40[^1].
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