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Stats II · Most repeated questions

74 questions · 192 marks · 7 papers · 26 question types

Answer key

Indian Institute of Technology Madras

BS Degree Programme · Examination & Study Paper

Statistics for Data Science II

Most repeated questions

Official Paper

Examination Instructions & Guidelines

Solve on notebook/paper first before checking solutions.
MCQ: Exactly 1 option is correct. Negative marking applies.
MSQ: One or more options correct. Select all to score.
NAT: Numerical response. No negative marking.
Scientific calculator allowed for all calculations.
Official answer key is sealed at the end of this sheet.

Type 1 · asked 5 times · Joint, marginal & conditional

Find the marginal distribution from a joint PDF or PMF

Read the passage below, then answer Q1
Based on the above data, answer the given subquestions.
Q1MCQ2 Marks·Choose one option
End Term · 22 Dec 2024 (AN)Key ↓
Find the Marginal distribution of X.
1. A
2. B
3. C
4. D
Read the passage below, then answer Q2
Based on the above data, answer the given subquestions.
Q2MCQ2 Marks·Choose one option
End Term · 22 Dec 2024 (FN)Key ↓
1. A
2. B
3. C
4. D
Read the passage below, then answer Q3
The joint density function of two continuous random variables X and Y is given as:
Based on the above data, answer the given subquestions.
Q3MCQ2 Marks·Choose one option
End Term · 13 Apr 2025 (AN)Key ↓
Find the marginal probability density function of X.
1. A
2. B
3. C
4. D
Useful Reference Data for this Paper
Read the passage below, then answer Q4
Based on the above data, answer the given subquestions.
Q4MCQ3 Marks·Choose one option
Quiz 2 · 3 Aug 2025 (AN)Key ↓
1. A
2. B
3. C
4. D
Read the passage below, then answer Q5
Based on the above data, answer the given subquestions.
Q5MCQ2 Marks·Choose one option
Quiz 2 · 3 Aug 2025 (AN)Key ↓
What is the marginal distribution of Y ?
1. A
2. B
3. C
4. D

Type 2 · asked 5 times · Method of moments & MLE

Find the method of moments estimate of a parameter from a sample

Read the passage below, then answer Q6
Based on the above data, answer the given subquestions.
Q6NAT3 Marks·Write the number
End Term · 22 Dec 2024 (AN)Key ↓
Your answer:
Q7NAT3 Marks·Write the number
End Term · 22 Dec 2024 (FN)Key ↓
Your answer:
Read the passage below, then answer Q8
Based on the above data, answer the given subquestions.
Q8NAT2 Marks·Write the number
End Term · 22 Dec 2024 (FN)Key ↓
Consider a random sample (1, 0, 1, 2, 2, 0, 1). Find the method of moments estimate of θ for the given sample. Enter the answer correct to two decimal places.
Your answer:
Read the passage below, then answer Q9
Based on the above data, answer the given subquestions.
Q9NAT4 Marks·Write the number
End Term · 13 Apr 2025 (FN)Key ↓
Find the method of moments estimate of θ for the given sample.
Your answer:
Q10MCQ3 Marks·Choose one option
End Term · 31 Aug 2025 (FN)Key ↓
1. A
2. B
3. C
4. D

Type 3 · asked 4 times · Joint, marginal & conditional

Find a conditional probability or density from a joint distribution

Read the passage below, then answer Q11
The joint density function of two continuous random variables X and Y is given as:
Based on the above data, answer the given subquestions.
Q11NAT3 Marks·Write the number
End Term · 13 Apr 2025 (AN)Key ↓
Your answer:
Useful Reference Data for this Paper
Q12NAT3 Marks·Write the number
Quiz 2 · 3 Aug 2025 (AN)Key ↓
Your answer:
Read the passage below, then answer Q13
Based on the above data, answer the given subquestions.
Q13NAT3 Marks·Write the number
Quiz 2 · 3 Aug 2025 (AN)Key ↓
Your answer:
Read the passage below, then answer Q14
Based on the above data, answer the given subquestions.
Q14NAT3 Marks·Write the number
End Term · 31 Aug 2025 (FN)Key ↓
Your answer:

Type 4 · asked 4 times · Continuous random variables

Find the constant k that makes a PDF or PMF valid

Read the passage below, then answer Q15
Based on the above data, answer the given subquestions.
Q15NAT1 Mark·Write the number
End Term · 13 Apr 2025 (FN)Key ↓
Your answer:
Useful Reference Data for this Paper
Read the passage below, then answer Q16
Based on the above data, answer the given subquestions.
Q16NAT2 Marks·Write the number
Quiz 2 · 3 Aug 2025 (AN)Key ↓
Find the value of k.
Your answer:
Read the passage below, then answer Q17
Based on the above data, answer the given subquestions.
Q17MCQ2 Marks·Choose one option
End Term · 31 Aug 2025 (FN)Key ↓
Find the value of k .
1. A17
2. B18
3. C1/17
4. D1/18
Useful Reference Data for this Paper
Read the passage below, then answer Q18
Based on the above data, answer the given subquestions.
Q18MCQ2 Marks·Choose one option
Quiz 1 · 26 Oct 2025 (AN)Key ↓
Find the value of k.
1. A
2. B
3. C
4. D

Type 5 · asked 4 times · Estimators: bias & variance

Check bias, variance and consistency of given estimators

Q19MSQ3 Marks·Choose all correct options
End Term · 22 Dec 2024 (AN)Key ↓
1. A
2. B
3. C
4. D
Q20MSQ3 Marks·Choose all correct options
End Term · 22 Dec 2024 (FN)Key ↓
1. A
2. B
3. C
4. D
Q21MSQ3 Marks·Choose all correct options
End Term · 13 Apr 2025 (AN)Key ↓
1. A
2. B
3. C
4. D
5. E
Q22MSQ3 Marks·Choose all correct options
End Term · 13 Apr 2025 (FN)Key ↓
1. A
2. B
3. C
4. D
5. E

Type 6 · asked 4 times · Method of moments & MLE

Find the maximum likelihood estimate of theta from a sample

Q23NAT3 Marks·Write the number
End Term · 22 Dec 2024 (AN)Key ↓
Your answer:
Read the passage below, then answer Q24
Based on the above data, answer the given subquestions.
Q24NAT2 Marks·Write the number
End Term · 22 Dec 2024 (AN)Key ↓
Your answer:
Read the passage below, then answer Q25
Based on the above data, answer the given subquestions.
Q25NAT3 Marks·Write the number
End Term · 22 Dec 2024 (FN)Key ↓
Consider a random sample (2, 0, 1, 1, 2, 2, 1, 1, 0, 0). Find the maximum likelihood estimate of θ for the given sample. Enter the answer correct to one decimal place.
Your answer:
Read the passage below, then answer Q26
Based on the above data, answer the given subquestions.
Q26MCQ2 Marks·Choose one option
End Term · 31 Aug 2025 (FN)Key ↓
What is the maximum likelihood estimate of θ?
1. A
2. B
3. C
4. D

Type 7 · asked 4 times · Bayesian estimation

Find the Beta posterior of a proportion p from survey data

Read the passage below, then answer Q27
Let p be the true proportion of customers who favor a newly introduced feature in our mobile app. The product team randomly selected 50 customers and asked them if they appreciate the new feature. From the survey, 20 out of the 50 customers responded with a ‘yes’.
Based on the above data, answer the given subquestions.
Q27MCQ3 Marks·Choose one option
End Term · 22 Dec 2024 (AN)Key ↓
Find the posterior distribution of p for a Uniform [0, 1] prior.
1. ABeta(20, 30)
2. BBeta(30, 20)
3. CBeta(21, 31)
4. DBeta(31, 21)
Read the passage below, then answer Q28
A company is testing a new AI-based chatbot for customer service and wants to know if it is liked by its users. Let p be the true proportion of users who would find the chatbot helpful. The team selected 30 customers randomly and asked if they found the chatbot useful. Out of these, 12 responded ‘yes’.
Based on the above data, answer the given subquestions.
Q28MCQ3 Marks·Choose one option
End Term · 22 Dec 2024 (FN)Key ↓
Find the posterior distribution of p for a Beta [3, 2] prior.
1. ABeta(12, 18)
2. BBeta(15, 20)
3. CBeta(14, 19)
4. DBeta(20, 15)
Read the passage below, then answer Q29
A software company is analyzing the bug reports for their newly developed application. Some bug reports identify a critical bug in the application. To estimate the probability p of a bug report identifying a critical bug, they collect a random sample of 200 bug reports, and find that 50 are classified as critical. The company adopts a Bayesian approach with a Beta distribution as the prior for p.
Based on the above data, answer the given subquestions.
Q29MCQ1 Mark·Choose one option
End Term · 13 Apr 2025 (FN)Key ↓
Using the prior distribution and the observed data, compute the posterior distribution of p.
1. ABeta(50.4, 154.6)
2. BBeta(1.4, 5.6)
3. CBeta(5.6, 1.4)
4. DBeta(51.4, 155.6)
Q30MCQ3 Marks·Choose one option
End Term · 31 Aug 2025 (FN)Key ↓
1. ABeta (29, 44)
2. BBeta (30, 45)
3. CBeta (20, 30)
4. DBeta (10, 15)

Type 8 · asked 4 times · Hypothesis testing

State the null and alternative hypotheses for a claim about a mean

Read the passage below, then answer Q31
A packaging company uses a machine to fill packets with 98.5 gram of powdered material. A quality control manager suspects that the machine is underfilling the packets. To investigate, he collects a random sample of 100 packets and measures the weights. The sample reveals an average weight of 98.29 gram, with a standard deviation of 1.2 gram.
Based on the above data, answer the given subquestions.
Q31MCQ2 Marks·Choose one option
End Term · 22 Dec 2024 (AN)Key ↓
State the null and alternative hypotheses.
1. A
2. B
3. C
4. D
Read the passage below, then answer Q32
The average battery life of smartphones for a certain model is 15 hours, with a standard deviation of 3 hours. An analyst suspects that the true average battery life is greater
than 15 hours. To test this, he takes a random sample of 100 smartphones and finds that the sample mean battery life is 17 hours.
Based on the above data, answer the given subquestions.
Q32MCQ2 Marks·Choose one option
End Term · 22 Dec 2024 (FN)Key ↓
State the null and alternative hypotheses.
1. A
2. B
3. C
4. D
Read the passage below, then answer Q33
Based on the above data, answer the given subquestions.
Q33MCQ2 Marks·Choose one option
End Term · 13 Apr 2025 (AN)Key ↓
State the null and alternative hypotheses.
1. A
2. B
3. C
4. D
Read the passage below, then answer Q34
A tech company claims that the average time their employees take to solve a debugging task is 45 minutes, with a known standard deviation of 10 minutes. A skeptical manager believes this time is too high and takes a random sample of 64 tasks. The manager decides to reject the company’s claim if the sample average time is less than ‘c’ minutes. Based on the given information, answer the subquestions.
Q34MCQ2 Marks·Choose one option
End Term · 31 Aug 2025 (FN)Key ↓
Define null and alternative hypotheses.
1. A
2. B
3. C
4. D

Type 9 · asked 3 times · Functions of random variables

Find the PMF or possible values of Z = g(X, Y) from given PMFs

Read the passage below, then answer Q35
Based on the above data, answer the given subquestions.
Q35MCQ3 Marks·Choose one option
End Term · 22 Dec 2024 (AN)Key ↓
1. A
2. B
3. C
4. D
Read the passage below, then answer Q36
Based on the above data, answer the given subquestions.
Q36MCQ3 Marks·Choose one option
End Term · 22 Dec 2024 (FN)Key ↓
1. A
2. B
3. C
4. D
Read the passage below, then answer Q37
A factory produces electronic processors and their performance score depends on two factors: (i) Number of Cores (X), (ii) Cache Size (Y ). For a randomly chosen processor, the probability mass functions (PMFs) of X and Y are given as follows:
The overall performance score (Z) of a processor is defined as Z= 4X + 3Y .
Based on the above data, answer the given subquestions.
Q37MCQ2 Marks·Choose one option
End Term · 13 Apr 2025 (AN)Key ↓
Identify all the possible values of overall performance score (Z).
1. A{10, 13, 14, 16, 17, 20}
2. B{11, 13, 19, 14, 18, 25}
3. C{10, 11, 14, 16, 19, 20}
4. D{11, 14, 15, 18, 19, 22}

Type 10 · asked 3 times · Functions of random variables

Find E[Z] for Z = g(X, Y) from given PMFs

Read the passage below, then answer Q38
Based on the above data, answer the given subquestions.
Q38NAT2 Marks·Write the number
End Term · 22 Dec 2024 (AN)Key ↓
Your answer:
Read the passage below, then answer Q39
Based on the above data, answer the given subquestions.
Q39NAT2 Marks·Write the number
End Term · 22 Dec 2024 (FN)Key ↓
Your answer:
Read the passage below, then answer Q40
A factory produces electronic processors and their performance score depends on two factors: (i) Number of Cores (X), (ii) Cache Size (Y ). For a randomly chosen processor, the probability mass functions (PMFs) of X and Y are given as follows:
The overall performance score (Z) of a processor is defined as Z= 4X + 3Y .
Based on the above data, answer the given subquestions.
Q40NAT3 Marks·Write the number
End Term · 13 Apr 2025 (AN)Key ↓
Compute the value of E [ Z ]. Enter the answer correct to one decimal place.
Your answer:

Type 11 · asked 3 times · Bayesian estimation

Find the Gamma posterior of a Poisson rate lambda

Q41MCQ3 Marks·Choose one option
End Term · 13 Apr 2025 (AN)Key ↓
1. AGamma (145, 12)
2. BGamma (12, 145)
3. CGamma (145, 72)
4. DGamma (72, 145)
Read the passage below, then answer Q42
Based on the above data, answer the given subquestions.
Q42MCQ2 Marks·Choose one option
End Term · 13 Apr 2025 (AN)Key ↓
Assume the prior distribution of λ to be Gamma(2,2). Determine the posterior distribution of λ.
1. AGamma(7, 7.4)
2. BGamma(6.4, 7)
3. CGamma(7, 6.4)
4. DGamma(7.4, 7)
Read the passage below, then answer Q43
A research team is analyzing customer complaints per day for a new service. The number of complaints X follows a Poisson distribution with an unknown average rate λ. The number of complaints observed over a period of 10 days are as follows :
3, 5, 2, 4, 6, 3, 4, 7, 5, 4
The team aims to estimate λ using two different methods: Maximum Likelihood Estimation (MLE) and Bayesian Estimation.
Based on the above data, answer the given subquestions.
Q43MCQ2 Marks·Choose one option
End Term · 13 Apr 2025 (FN)Key ↓
Assume the prior distribution of λ to be Gamma(3, 2). Determine the posterior distribution of λ.
1. AGamma(45, 12)
2. BGamma(12, 46)
3. CGamma(46, 12)
4. DGamma(12, 45)

Type 12 · asked 3 times · Hypothesis testing

Find the critical value c or rejection probability for a z-test

Q44NAT3 Marks·Write the number
End Term · 13 Apr 2025 (FN)Key ↓
Your answer:
Q45NAT3 Marks·Write the number
End Term · 31 Aug 2025 (FN)Key ↓
Your answer:
Read the passage below, then answer Q46
A tech company claims that the average time their employees take to solve a debugging task is 45 minutes, with a known standard deviation of 10 minutes. A skeptical manager believes this time is too high and takes a random sample of 64 tasks. The manager decides to reject the company’s claim if the sample average time is less than ‘c’ minutes. Based on the given information, answer the subquestions.
Q46NAT3 Marks·Write the number
End Term · 31 Aug 2025 (FN)Key ↓
If the value of the significance level is 0.16, then find the value of ‘c’. Enter the answer correct to two decimal places.
Your answer:

Type 13 · asked 2 times · Joint, marginal & conditional

Find a region probability like P(X + Y <= 1) from a joint PDF

Read the passage below, then answer Q47
Based on the above data, answer the given subquestions.
Q47NAT3 Marks·Write the number
End Term · 22 Dec 2024 (AN)Key ↓
Your answer:
Useful Reference Data for this Paper
Read the passage below, then answer Q48
Based on the above data, answer the given subquestions.
Q48NAT2 Marks·Write the number
Quiz 2 · 3 Aug 2025 (AN)Key ↓
Find the value of P(X < 1, Y < 1). Enter the answer correct to two decimal places.
Your answer:

Type 14 · asked 2 times · Functions of random variables

Find P(X^2 < a) or P(X^2 > a) for a normal X using the standard normal

Q49MCQ3 Marks·Choose one option
End Term · 22 Dec 2024 (FN)Key ↓
1. A
2. B
3. C
4. D
Useful Reference Data for this Paper
Q50MCQ3 Marks·Choose one option
Quiz 2 · 3 Aug 2025 (AN)Key ↓
1. A
2. B
3. C
4. D

Type 15 · asked 2 times · Continuous random variables

Find P(a < X < b) from a given PDF

Read the passage below, then answer Q51
Based on the above data, answer the given subquestions.
Q51NAT2 Marks·Write the number
End Term · 13 Apr 2025 (FN)Key ↓
Your answer:
Useful Reference Data for this Paper
Read the passage below, then answer Q52
Based on the above data, answer the given subquestions.
Q52NAT3 Marks·Write the number
Quiz 2 · 3 Aug 2025 (AN)Key ↓
Your answer:

Type 16 · asked 2 times · Continuous random variables

Find a conditional probability P(X in A | X > c) for continuous X

Q53NAT3 Marks·Write the number
End Term · 13 Apr 2025 (AN)Key ↓
Your answer:
Useful Reference Data for this Paper
Read the passage below, then answer Q54
Based on the above data, answer the given subquestions.
Q54NAT3 Marks·Write the number
Quiz 1 · 26 Oct 2025 (AN)Key ↓
Your answer:

Type 17 · asked 2 times · Expectation, variance & covariance

Find an unknown PMF value when E[X] is given

Read the passage below, then answer Q55
Based on the above data, answer the given subquestions.
Q55NAT3 Marks·Write the number
End Term · 13 Apr 2025 (FN)Key ↓
Your answer:
Useful Reference Data for this Paper
Q56NAT3 Marks·Write the number
Quiz 1 · 26 Oct 2025 (AN)Key ↓
Your answer:

Type 18 · asked 2 times · Expectation, variance & covariance

Use expectation and variance rules for combinations of RVs

Useful Reference Data for this Paper
Q57MSQ3 Marks·Choose all correct options
Quiz 2 · 3 Aug 2025 (AN)Key ↓
1. A
2. B
3. C
4. D
Useful Reference Data for this Paper
Q58NAT3 Marks·Write the number
Quiz 1 · 26 Oct 2025 (AN)Key ↓
Your answer:

Type 19 · asked 2 times · Inequalities, MGF & CLT

Find a lower bound on a probability with Chebyshev's inequality

Useful Reference Data for this Paper
Read the passage below, then answer Q59
Based on the above data, answer the given subquestions.
Q59NAT2 Marks·Write the number
Quiz 2 · 3 Aug 2025 (AN)Key ↓
Your answer:
Useful Reference Data for this Paper
Read the passage below, then answer Q60
Based on the above data, answer the given subquestions.
Q60NAT3 Marks·Write the number
Quiz 1 · 26 Oct 2025 (AN)Key ↓
Using Chebyshev’s inequality, find a lower bound on the probability that the processing time lies between 480 milliseconds and 520 milliseconds. Enter the answer correct to two decimal places.
Your answer:

Type 20 · asked 2 times · Method of moments & MLE

Find the MLE of a Poisson rate lambda from a sample

Read the passage below, then answer Q61
Based on the above data, answer the given subquestions.
Q61NAT3 Marks·Write the number
End Term · 13 Apr 2025 (AN)Key ↓
Find the maximum likelihood estimate of λ for the given sample. Enter the answer correct to two decimal places.
Your answer:
Read the passage below, then answer Q62
A research team is analyzing customer complaints per day for a new service. The number of complaints X follows a Poisson distribution with an unknown average rate λ. The number of complaints observed over a period of 10 days are as follows :
3, 5, 2, 4, 6, 3, 4, 7, 5, 4
The team aims to estimate λ using two different methods: Maximum Likelihood Estimation (MLE) and Bayesian Estimation.
Based on the above data, answer the given subquestions.
Q62NAT3 Marks·Write the number
End Term · 13 Apr 2025 (FN)Key ↓
Find the maximum likelihood estimate of λ for the given sample. Enter the answer correct to one decimal place.
Your answer:

Type 21 · asked 2 times · Bayesian estimation

Find the posterior mean of p from a Beta posterior

Read the passage below, then answer Q63
Let p be the true proportion of customers who favor a newly introduced feature in our mobile app. The product team randomly selected 50 customers and asked them if they appreciate the new feature. From the survey, 20 out of the 50 customers responded with a ‘yes’.
Based on the above data, answer the given subquestions.
Q63NAT2 Marks·Write the number
End Term · 22 Dec 2024 (AN)Key ↓
Find the posterior mean. Enter the answer correct to two decimal places.
Your answer:
Read the passage below, then answer Q64
A company is testing a new AI-based chatbot for customer service and wants to know if it is liked by its users. Let p be the true proportion of users who would find the chatbot helpful. The team selected 30 customers randomly and asked if they found the chatbot useful. Out of these, 12 responded ‘yes’.
Based on the above data, answer the given subquestions.
Q64NAT2 Marks·Write the number
End Term · 22 Dec 2024 (FN)Key ↓
Find the posterior mean using the correct prior from the previous question. Enter the answer correct to two decimal places.
Your answer:

Type 22 · asked 2 times · Bayesian estimation

Choose a prior parameter that gives a stated prior mean

Read the passage below, then answer Q65
Based on the above data, answer the given subquestions.
Q65MCQ2 Marks·Choose one option
End Term · 13 Apr 2025 (AN)Key ↓
1. A
2. B
3. C
4. D
Read the passage below, then answer Q66
A software company is analyzing the bug reports for their newly developed application. Some bug reports identify a critical bug in the application. To estimate the probability p of a bug report identifying a critical bug, they collect a random sample of 200 bug reports, and find that 50 are classified as critical. The company adopts a Bayesian approach with a Beta distribution as the prior for p.
Based on the above data, answer the given subquestions.
Q66MCQ2 Marks·Choose one option
End Term · 13 Apr 2025 (FN)Key ↓
The company assumes a Beta(1.4, b) prior for p. Given that prior knowledge suggests the expected value of p is approximately 0.2, determine the appropriate value of b.
1. A
2. B
3. C
4. D

Type 23 · asked 2 times · Bayesian estimation

Given the posterior mean, find an unknown prior or data parameter

Read the passage below, then answer Q67
Based on the above data, answer the given subquestions.
Q67NAT3 Marks·Write the number
End Term · 13 Apr 2025 (AN)Key ↓
Your answer:
Read the passage below, then answer Q68
Based on the above data, answer the given subquestions.
Q68NAT2 Marks·Write the number
End Term · 31 Aug 2025 (FN)Key ↓
If the posterior mean is 0.6, then find the value of m.
Your answer:

Type 24 · asked 2 times · Hypothesis testing

True statements about power and Type I / Type II errors

Q69MSQ3 Marks·Choose all correct options
End Term · 22 Dec 2024 (AN)Key ↓
Which of the following statement(s) is(are) correct?
1. AThe power of a test is the probability of rejecting the null hypothesis when it is false.
2. BThe probability of accepting the alternative hypothesis when it is true is called as level of significance.
3. CType I error is the probability of rejecting the null hypothesis when alternative hypothesis is false.
4. DIf the probability of making a Type II error is 0.05, the power of the test is 0.95.
Q70MSQ3 Marks·Choose all correct options
End Term · 22 Dec 2024 (FN)Key ↓
Which of the following statement(s) is(are) correct?
1. AThe power of a test is the probability of rejecting the null hypothesis when it is false.
2. BThe probability of accepting the alternative hypothesis when it is true is called as level of significance.
3. CType I error is the probability of rejecting the null hypothesis when alternative hypothesis is false.
4. DIf the probability of making a Type II error is 0.05, the power of the test is 0.95.

Type 25 · asked 2 times · Hypothesis testing

Decide to reject or accept H0 at given significance levels

Read the passage below, then answer Q71
A packaging company uses a machine to fill packets with 98.5 gram of powdered material. A quality control manager suspects that the machine is underfilling the packets. To investigate, he collects a random sample of 100 packets and measures the weights. The sample reveals an average weight of 98.29 gram, with a standard deviation of 1.2 gram.
Based on the above data, answer the given subquestions.
Q71MSQ3 Marks·Choose all correct options
End Term · 22 Dec 2024 (AN)Key ↓
Choose the set of correct options.
1. A
2. B
3. C
4. D
Read the passage below, then answer Q72
The average battery life of smartphones for a certain model is 15 hours, with a standard deviation of 3 hours. An analyst suspects that the true average battery life is greater
than 15 hours. To test this, he takes a random sample of 100 smartphones and finds that the sample mean battery life is 17 hours.
Based on the above data, answer the given subquestions.
Q72MCQ3 Marks·Choose one option
End Term · 22 Dec 2024 (FN)Key ↓
What conclusion will you make for the given test?
1. A
2. B

Type 26 · asked 2 times · Hypothesis testing

Write the significance level of a test in terms of c

Q73MCQ3 Marks·Choose one option
End Term · 13 Apr 2025 (AN)Key ↓
1. A
2. B
3. C
4. D
Q74MCQ3 Marks·Choose one option
End Term · 13 Apr 2025 (FN)Key ↓
1. A
2. B
3. C
4. D

Official Key

Master Answer Key & Explanations

Official answer keys from IIT Madras BS past papers. Click any question to review.

Reveal Key

Q1B

Q2B

Q3B

Q4D

Q5B

Q60.57 to 0.63

Q70.14 to 0.2

Q80.4 to 0.46

Q94

Q10A

Q110.3 to 0.36

Q120.22 to 0.28

Q130.42 to 0.48

Q140.8 to 0.86

Q153

Q164

Q17B

Q18B

Q19A, D

Q20B, C

Q21A, C, D

Q22B, C, E

Q230.16 to 0.22

Q240.69 to 0.75

Q250.27 to 0.33

Q26B

Q27C

Q28B

Q29D

Q30B

Q31C

Q32A

Q33C

Q34B

Q35C

Q36B

Q37D

Q381.3 to 1.36

Q391.75 to 1.81

Q4016 to 16.4

Q41C

Q42A

Q43C

Q4421.62 to 21.68

Q450.01 to 0.03

Q4643.73 to 43.79

Q470.3 to 0.36

Q480.29 to 0.35

Q49C

Q50D

Q510.114 to 0.12

Q520.41 to 0.47

Q530.22 to 0.28

Q540.6 to 0.66

Q556

Q560.1

Q57B, D

Q58638

Q590.75 to 0.81

Q600.73 to 0.77

Q610.9 to 0.96

Q624.1 to 4.5

Q630.37 to 0.43

Q640.4 to 0.46

Q65A

Q66C

Q672.64 to 2.7

Q682

Q69A, C, D

Q70A, C, D

Q71A, B

Q72A

Q73D

Q74A

Questions and answer keys are reproduced from the official IIT Madras BS papers. Topics and repeated question types are BTechi’s own grouping. BTechi is not affiliated with IIT Madras.