CUET UG Applied Mathematics Booster Test 1 - Population & Sample
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QUESTION 1 OF 20
Which of the following describe a parameter in relation to a population?
Statements:
I. It is a numerical value computed from all population observations.
II. It is a characteristic strictly belonging to a sample.
III. It is commonly denoted by Greek symbols (e.g., μ, Ļ).
QUESTION 2 OF 20
In a continuous setting, the population size N is modeled by:
\(N=\int_{0}^{2}\,3x^{2}dx\)
QUESTION 3 OF 20
Match List I with List II:
| List I | List II |
|---|---|
| 1. μ | a. Population mean |
| 2. xĢ | b. Sample mean |
| 3. Ļ | c. Population standard deviation |
| 4. S | d. Sample standard deviation |
QUESTION 4 OF 20
Arrange progression from broadest to most specific:
I. Statistic
II. Sample
III. Parameter
IV. Population
QUESTION 5 OF 20
Assertion (A): It is nearly impossible to conduct clinical trials on an entire country's population.
Reason (R): Large populations involve constraints of time, cost, and logistics, requiring sampling.
QUESTION 6 OF 20
Find expected value of vector:
Let:
\(\vec{X}=[\hat{x}_{1},\hat{x}_{2},\hat{x}_{3}],withĀ E[\hat{x}_{i}]=\mu\)
Find:
\(E[\vec{X}]\)
QUESTION 7 OF 20
According to the Central Limit Theorem, as sample size \(n\) increases, the sampling distribution:
QUESTION 8 OF 20
A 95% confidence interval represents the central area under a normal curve.
What is the combined area in the two tails?
QUESTION 9 OF 20
Data: \(10,15,20,25,30\)
3-week moving averages:
\(\frac{10+15+20}{3}=15,\frac{15+20+25}{3}=20,\frac{20+25+30}{3}=25\)
QUESTION 10 OF 20
From \(N=1000\), what is the probability a specific item is not selected on the first draw?
QUESTION 11 OF 20
From N=10, choose n=3:
(10¦3)
QUESTION 12 OF 20
Which mathematical statement is theoretically incorrect regarding determining sample size n and degrees of freedom Df?
QUESTION 13 OF 20
When performing a one-sample t-test, if the recorded sample size is N, the degrees of freedom Df used is:
QUESTION 14 OF 20
Sampling error can be positive or negative and decreases as the sample size increases.
Mathematically:
"Sampling Error"=x Ė-μ
Causes include:
Small sample size
Faulty selection
Natural variability in outcomes
QUESTION 15 OF 20
Sampling error can be positive or negative and decreases as the sample size increases.
Mathematically:
"Sampling Error"=x Ė-μ
Causes include:
Small sample size
Faulty selection
Natural variability in outcomes
QUESTION 16 OF 20
Sampling method where students selected by last digit "2":
QUESTION 17 OF 20
Assertion (A): A representative sample perfectly captures every unique characteristic of all population members.
Reason (R): A representative sample only needs to reflect key features of the population in an unbiased way.
QUESTION 18 OF 20
Which traits apply to unrepresentative sample?
I. It is a perfectly unbiased reflection of the population
II. The sample statistic does not accurately represent the population parameter
III. It leads to selection bias
QUESTION 19 OF 20
Match the sampling methods with their corresponding characteristics.
| List I | List II |
|---|---|
| 1. Simple Random Sampling | a. Every individual is selected purely by chance |
| 2. Systematic Random Sampling | b. Members are selected at fixed regular intervals |
| 3. Lottery Method | c. Each unit has an equal probability of being selected |
| 4. Sampling Interval | d. Every kth unit is selected after a random start |
QUESTION 20 OF 20
Which statement is incorrect regarding biased sampling?
Test Complete!
Answer Review
1 Which of the following describe a parameter in relation to a population?
Statements:
I. It is a numerical value computed from all population observations.
II. It is a characteristic strictly belonging to a sample.
III. It is commonly denoted by Greek symbols (e.g., μ, Ļ).
A parameter is a numerical characteristic of an entire population. It is usually represented by Greek letters, such as μ (population mean) and Ļ (population standard deviation).
A parameter summarizes a characteristic of the entire population, not just a sample. Statement I: ā True A parameter is calculated using all observations in the population. Example: The mean height of every student in a school is a population parameter. Statement II: ā False A characteristic of a sample is called a statistic, not a parameter. Statement III: ā True Population parameters are commonly represented using Greek symbols, such as: μ = Population mean Ļ = Population standard deviation ϲ = Population variance Therefore, the correct combination is I and III, making Option C the correct answer.
- Option A) I and II ā Incorrect because Statement II refers to a sample statistic, not a population parameter.
- Option B) II and III ā Incorrect because Statement II is false.
- Option D) I, II, and III ā Incorrect because Statement II is false.
Used
- Conceptual Recall
Application: Distinguish between a population parameter and a sample statistic, and recall the standard notation used in statistics.
Final Logic: Since Statements I and III are true, the correct answer is Option C.
Statistic = Sample = Roman letters (e.g., xĢ, s)
2 In a continuous setting, the population size N is modeled by:
\(N=\int_{0}^{2}\,3x^{2}dx\)
Integrate polynomial Apply limits 0 to 2 Compute definite integral
- \(\int 3x^{2}dx=x^{3}\). Evaluating from 0 to 2: \(2^{3}-0=8\)
- Option A ā Incorrect evaluation
- Option C ā Overestimation
- Option D ā Wrong integration result
Used: Substitution
Application: Direct integral evaluation
Final Logic: x³ evaluated at bounds
"3x² ā x³ shortcut"
3 Match List I with List II:
| List I | List II |
|---|---|
| 1. μ | a. Population mean |
| 2. xĢ | b. Sample mean |
| 3. Ļ | c. Population standard deviation |
| 4. S | d. Sample standard deviation |
μ = population mean xĢ = sample mean Ļ = population SD S = sample SD
- Standard statistical notation mapping directly defines population and sample measures.
- Option B ā Mislabels mean/SD
- Option C ā Completely reversed mapping
- Option D ā Incorrect swapping
Used: Option Grouping
Application: Symbol-definition pairing
Final Logic: Standard statistical notation
"Greek = population, Latin = sample"
4 Arrange progression from broadest to most specific:
I. Statistic
II. Sample
III. Parameter
IV. Population
Population is largest set Sample is subset Parameter describes population Statistic describes sample
- Population ā Parameter ā Sample ā Statistic represents hierarchy from general to specific inference levels.
- Option A ā reverse order
- Option B ā incorrect grouping
- Option C ā mismatched hierarchy
Used: Logical Ordering
Application: Hierarchical arrangement
Final Logic: population ā sample flow
"Big ā Small ā Measure"
5 Assertion (A): It is nearly impossible to conduct clinical trials on an entire country's population.
Reason (R): Large populations involve constraints of time, cost, and logistics, requiring sampling.
Clinical trials are costly Full population studies impractical Sampling reduces burden
- Large populations require sampling due to cost, time, and feasibility constraints.
- Option A ā Both statements are true
- Option B ā Reason is valid
- Option D ā Incorrect relationship
Used: CauseāEffect Matching
Application: Link practicality with sampling need
Final Logic: constraints justify sampling
"Big population ā sample solution"
6 Find expected value of vector:
Let:
\(\vec{X}=[\hat{x}_{1},\hat{x}_{2},\hat{x}_{3}],withĀ E[\hat{x}_{i}]=\mu\)
Find:
\(E[\vec{X}]\)
Expectation distributes linearly Each component equals μ Vector expectation becomes uniform
- Since E[xĢįµ¢] = μ, expectation of vector becomes [μ, μ, μ].
- Option A ā incomplete vector
- Option C ā mismatched components
- Option D ā invalid transformation
Used: Substitution
Application: Apply expectation operator component-wise
Final Logic: linearity of expectation
"E spreads evenly"
7 According to the Central Limit Theorem, as sample size \(n\) increases, the sampling distribution:
CLT governs distribution shape Larger samples normalize distribution Approaches Gaussian form
- Central Limit Theorem states sampling distribution tends toward normality as n increases.
- Option A ā incorrect flattening
- Option C ā false exact match claim
- Option D ā opposite behavior
Used: Theoretical Recall
Application: CLT property recognition
Final Logic: convergence to normal curve
"Big n ā Bell curve"
8 A 95% confidence interval represents the central area under a normal curve.
What is the combined area in the two tails?
Central area = 95% Remaining area = tails Split equally across two tails
- Total probability is 1, so outside 95% interval is 0.05.
- Option B ā incorrect total tail sum
- Option C ā central value
- Option D ā single tail value
Used: Complement Rule
Application: 1 ā 0.95
Final Logic: tail probability = 0.05
"100 ā 95 = 5"
9 Data: \(10,15,20,25,30\)
3-week moving averages:
\(\frac{10+15+20}{3}=15,\frac{15+20+25}{3}=20,\frac{20+25+30}{3}=25\)
Average consecutive triplets Sliding window method Produces smoothed series
- (10+15+20)/3 = 15, (15+20+25)/3 = 20, (20+25+30)/3 = 25.
- Option A ā incorrect arithmetic
- Option B ā raw data misuse
- Option D ā incorrect transformation
Used: Substitution
Application: Step-by-step averaging
Final Logic: sliding mean computation
"Add 3, divide 3"
10 From \(N=1000\), what is the probability a specific item is not selected on the first draw?
Only 1 selected out of 1000 Remaining are not selected Probability = complement
- Out of 1000 items, 999 remain unselected in first draw.
- Option A ā selection probability
- Option B ā irrelevant fraction
- Option C ā incorrect ratio
Used: Complement Principle
Application: 1 ā 1/1000
Final Logic: non-selection probability
"Total minus one"
11 From N=10, choose n=3:
(10¦3)
This is a combination problem: \(^{10}C_{3}\) Order does not matter Use formula \(n!/(r!(n-r)!)\)
- \(^{10}C_{3}=\frac{10!}{3!7!}=\frac{10\times 9\times 8}{3\times 2\times 1}=120\)
- Option B ā Not related to combinations
- Option C ā Incorrect factorial computation
- Option D ā Represents a product form, not combinations
Used: Substitution
Application: Directly apply combination formula
Final Logic: Correct value comes from standard nCr formula
"nCr = factorial cut-down multiplication"
12 Which mathematical statement is theoretically incorrect regarding determining sample size n and degrees of freedom Df?
Smaller samples increase error Larger samples improve accuracy Df increases with sample size
- Smaller sample sizes increase sampling error and reduce reliability. Accuracy improves with larger n, not smaller.
- Option A ā True: larger n increases df
- Option B ā True: df = n ā 1
- Option C ā True: CLT threshold rule
- Option D ā False: contradicts statistical principle
Used: Extreme Word Filter
Application: "improves accuracy" vs statistical reality
Final Logic: Smaller sample size worsens accuracy
"More data = more accuracy"
13 When performing a one-sample t-test, if the recorded sample size is N, the degrees of freedom Df used is:
t-test uses sample-based estimation One parameter estimated reduces freedom Hence df = n ā 1
- One degree of freedom is lost because the sample mean is estimated from the data.
- Option A ā Incorrect; ignores estimation constraint
- Option C ā No statistical basis
- Option D ā Irrelevant to df theory
Used: Conceptual Rule Recall
Application: Standard t-test formula recognition
Final Logic: df always reduces by 1 in one-sample t-test
"t-test ā take 1 away"
14
Sampling error can be positive or negative and decreases as the sample size increases.
Mathematically:
"Sampling Error"=x Ė-μ
Causes include:
Small sample size
Faulty selection
Natural variability in outcomes
Sampling error = sample mean ā population mean Can be positive or negative Measures deviation
- Sampling error is defined as the difference between sample statistic and population parameter.
- Option B ā Reversed sign only
- Option C ā Not a statistical measure
- Option D ā Ratio, not difference
Used: Definition Matching
Application: Direct passage extraction
Final Logic: error = estimate ā true value
"Error = Sample ā Population"
15
Sampling error can be positive or negative and decreases as the sample size increases.
Mathematically:
"Sampling Error"=x Ė-μ
Causes include:
Small sample size
Faulty selection
Natural variability in outcomes
Sampling error exists naturally Finite sample size causes deviation Even random sampling is imperfect
- Even random samples vary from population due to limited sample size and natural variability.
- Option A ā False assumption
- Option B ā Irrelevant concept
- Option D ā Statistically impossible
Used: Elimination
Application: Remove unrealistic absolute statements
Final Logic: finite samples always have variability
"Random ā perfect"
16 Sampling method where students selected by last digit "2":
Selection is rule-based, not random Not all members have equal chance Hence biased sampling
- Selecting based on digit pattern is not random and introduces bias.
- Option A ā requires interval-based selection
- Option B ā requires strata division
- Option D ā requires grouped clusters
Used: Contextual Matching
Application: Identify lack of randomness
Final Logic: fixed digit selection = bias
"Fixed rule = biased sample"
17 Assertion (A): A representative sample perfectly captures every unique characteristic of all population members.
Reason (R): A representative sample only needs to reflect key features of the population in an unbiased way.
Representative sample does NOT need perfect capture It should reflect population fairly Reason is correct
- Representative sample reflects key characteristics but does not perfectly replicate every feature.
- Option A ā false assertion
- Option B ā partially correct reasoning
- Option C ā mismatch in logic
Used: Logical Consistency Check
Application: Validate definition accuracy
Final Logic: representation ā perfection
"Representative ā identical"
18 Which traits apply to unrepresentative sample?
I. It is a perfectly unbiased reflection of the population
II. The sample statistic does not accurately represent the population parameter
III. It leads to selection bias
Not representative ā bias present Does not reflect population Leads to selection bias
- Unrepresentative samples fail to reflect population and introduce bias.
- Option A ā includes false claim I
- Option C ā includes false claim I
- Option D ā includes incorrect statement I
Used: Elimination
Application: Remove incorrect property I
Final Logic: bias + mismatch only
"Unrepresentative = biased + inaccurate"
19 Match the sampling methods with their corresponding characteristics.
| List I | List II |
|---|---|
| 1. Simple Random Sampling | a. Every individual is selected purely by chance |
| 2. Systematic Random Sampling | b. Members are selected at fixed regular intervals |
| 3. Lottery Method | c. Each unit has an equal probability of being selected |
| 4. Sampling Interval | d. Every kth unit is selected after a random start |
Simple random sampling is based entirely on chance. Systematic sampling selects units at fixed intervals. Lottery method gives every unit an equal chance of selection. A sampling interval refers to selecting every kth unit after a random start.
Sampling methods are used to select representative units from a population. In Simple Random Sampling, every individual in the population has an equal chance of being selected. One common method is the lottery method, where each unit has an equal probability of selection. Therefore, 1 ā a 3 ā c In Systematic Random Sampling, a random starting point is chosen, and then every kth unit is selected at fixed intervals throughout the population. Therefore, 2 ā b 4 ā d Thus, the correct matching is: 1 ā a 2 ā b 3 ā c 4 ā d Hence, Option A is correct.
- Option B ā Incorrect because it reverses the characteristics of simple random and systematic sampling.
- Option C ā Incorrect because it interchanges the definitions of the lottery method and simple random sampling.
- Option D ā Incorrect because the lottery method is not based on fixed intervals, and the sampling interval does not describe simple random sampling.
Used
- Option Grouping
- Application
- Identify the sampling method first, then associate it with its defining feature.
- Final Logic
- Simple Random Sampling ā Chance-based selection ā Equal probability.
- Systematic Random Sampling ā Random start ā Every kth unit.
"Lottery = Equal Chance"
20 Which statement is incorrect regarding biased sampling?
Biased sampling violates randomness Unequal selection probability Not uniform distribution
- Biased sampling does NOT ensure equal probability; that is a property of random sampling.
- Option A ā correct definition
- Option B ā true
- Option C ā true
Used: Extreme Word Filter
Application: "guarantees equal probability" is contradictory
Final Logic: bias ā equal chance
"Bias = unequal chance"
