BTechibtechi.in
Loading Loading
Free IIT Madras BS notes, PYQs and mock tests at btechi.in

Stats II · Hypothesis testing

26 questions · 58 marks · 5 papers

Answer key

Indian Institute of Technology Madras

BS Degree Programme · Examination & Study Paper

Statistics for Data Science II

Hypothesis testing

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.

End Term · 31 Aug 2025 (FN)End Term

Q1NAT3 Marks·Write the number
Asked 3 times Key ↓
Your answer:
Read the passage below, then answer Q2–Q7
Q2NAT0.5 Marks·Write the number
Key ↓
Your answer:
Q3NAT0.5 Marks·Write the number
Key ↓
Your answer:
Q4NAT0.5 Marks·Write the number
Key ↓
Your answer:
Q5NAT0.5 Marks·Write the number
Key ↓
Your answer:
Q6NAT0.5 Marks·Write the number
Key ↓
Your answer:
Q7NAT0.5 Marks·Write the number
Key ↓
Your answer:
Read the passage below, then answer Q8–Q9
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.
Q8MCQ2 Marks·Choose one option
Asked 4 times Key ↓
Define null and alternative hypotheses.
1. A
2. B
3. C
4. D
Q9NAT3 Marks·Write the number
Asked 3 times 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:

End Term · 13 Apr 2025 (FN)End Term

Q10MCQ3 Marks·Choose one option
Asked 2 times Key ↓
1. A
2. B
3. C
4. D
Q11NAT3 Marks·Write the number
Asked 3 times Key ↓
Your answer:
Read the passage below, then answer Q12–Q13
Based on the above data, answer the given subquestions.
Q12NAT3 Marks·Write the number
Key ↓
Your answer:
Q13NAT2 Marks·Write the number
Key ↓
Your answer:

End Term · 13 Apr 2025 (AN)End Term

Q14MCQ3 Marks·Choose one option
Key ↓
1. A
2. B
3. C
4. D
Q15MCQ3 Marks·Choose one option
Asked 2 times Key ↓
1. A
2. B
3. C
4. D
Read the passage below, then answer Q16–Q17
Based on the above data, answer the given subquestions.
Q16MCQ2 Marks·Choose one option
Asked 4 times Key ↓
State the null and alternative hypotheses.
1. A
2. B
3. C
4. D
Q17MCQ3 Marks·Choose one option
Key ↓
Suppose the researcher decides to increase the sample size 64 to 100 while keeping the same rejection threshold. What will be effect on level of significance?
1. AThe significance level will increase from 0.05 to 0.09.
2. BThe significance level will be same.
3. CThe significance level will decrease from 0.09 to 0.01.
4. DThe significance level will decrease from 0.09 to 0.05.

End Term · 22 Dec 2024 (FN)End Term

Q18MSQ3 Marks·Choose all correct options
Asked 2 times 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.
Q19MSQ3 Marks·Choose all correct options
Key ↓
1. A
2. B
3. C
4. D
Read the passage below, then answer Q20–Q21
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.
Q20MCQ2 Marks·Choose one option
Asked 4 times Key ↓
State the null and alternative hypotheses.
1. A
2. B
3. C
4. D
Q21MCQ3 Marks·Choose one option
Asked 2 times Key ↓
What conclusion will you make for the given test?
1. A
2. B

End Term · 22 Dec 2024 (AN)End Term

Q22MCQ3 Marks·Choose one option
Key ↓
1. A
2. B
3. C
4. D
Q23MCQ3 Marks·Choose one option
Key ↓
1. A
2. B
3. C
4. D
Q24MSQ3 Marks·Choose all correct options
Asked 2 times 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.
Read the passage below, then answer Q25–Q26
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.
Q25MCQ2 Marks·Choose one option
Asked 4 times Key ↓
State the null and alternative hypotheses.
1. A
2. B
3. C
4. D
Q26MSQ3 Marks·Choose all correct options
Asked 2 times Key ↓
Choose the set of correct options.
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

Q10.01 to 0.03

Q212

Q31

Q44

Q56

Q69

Q721.62 to 21.68

Q8B

Q943.73 to 43.79

Q10A

Q1121.62 to 21.68

Q120.06 to 0.12

Q130.95 to 1

Q14A

Q15D

Q16C

Q17D

Q18A, C, D

Q19B, D

Q20A

Q21A

Q22A

Q23A

Q24A, C, D

Q25C

Q26A, B

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.