CUET UG Applied Mathematics Booster Test 2 - Index Number Basics
π Answers are locked once submitted β results and explanations appear at the end.
QUESTION 1 OF 20
Q1. Concept of Index Number [Integral]
If the marginal change of an index number is modeled continuously over time as:
\(\frac{dI}{dt}=6t\)
and the base period index is given by
\(I(0)=100\)
find the index function
\(I(t)\)
using integration.
QUESTION 2 OF 20
Q2. Index as Measure of Change [Vector-Based Numerical]
Consider prices represented as a position vector:
\(\vec{r}=P_{0}\hat{i}+P_{n}\hat{j}\)
Given:
\(\vec{r}=30\hat{i}+46\hat{j}\)
representing wheat prices in 1997 and 2001 respectively, the price relative index is defined as:
\(\left(\frac{y-component}{x-component}\right)\times 100\)
Find the value of the index number.
QUESTION 3 OF 20
Q3. Relative Comparison Idea [Case/Numerical]
A departmental store spent βΉ1.3 lakh in 1990 and βΉ2.9 lakh in 2000 on newspaper advertisements. Using 1990 as the base year, find the price index for advertisement prices in 2000.
\(Index=\left(\frac{2.9}{1.3}\right)\times 100\)
QUESTION 4 OF 20
Q4. Base and Current Period [Probability]
Out of 5 available years (2000, 2001, 2002, 2003, 2004), a statistician randomly selects one year as the base period and one strictly subsequent year as the current period.
What is the probability that 2000 is chosen as the base period?
\(TotalΒ possibleΒ pairs=\left(\frac{5}{2}\right)=10\)
\(FavourableΒ cases=4\)
\(P=\frac{4}{10}\)
QUESTION 5 OF 20
Q5. Meaning of Index Series [Moving Average/Data]
For a 4-year moving average analysis, the 4-year moving totals are:
1730 and 1772
Find the centered total for these periods:
QUESTION 6 OF 20
Match List I with List II based on index number formulae.
| List I | List II |
|---|---|
| 1. Simple Aggregative | a. (Ξ£PnQn / Ξ£P0Qn) Γ 100 |
| 2. Simple Average of Relatives | b. (Ξ£Pn / Ξ£P0) Γ 100 |
| 3. Laspeyres' Index | c. (Ξ£PnQ0 / Ξ£P0Q0) Γ 100 |
| 4. Paasche's Index | d. [Ξ£((Pn / P0) Γ 100)] / N |
QUESTION 7 OF 20
Q7. CPI and GDP Indices [Multiple Correct]
Which of the following statements regarding Consumer Price Index (CPI) and GDP are correct?
(i) They are expressed as pure numbers.
(ii) They rely on absolute non-relative metrics.
(iii) They measure changes in general economic variables over time.
QUESTION 8 OF 20
QUESTION 9 OF 20
QUESTION 10 OF 20
Q10. Living Standard Measure [AssertionβReason]
Assertion (A): The Laspeyres index may overestimate the rise in the cost of living.
Reason (R): The Laspeyres index uses base-period weights, ignoring the possibility that consumers may reduce consumption of items that become relatively more expensive.
QUESTION 11 OF 20
Arrange the steps involved in forecasting using the method of least squares for fitting a straight line:
\(Y_{t}=a+bX\)
1. Compute
\(a=\frac{\sum Y}{n}\)
2. Set the midpoint of time as origin so that
\(\sum X=0\)
3. Compute
\(b=\frac{\sum XY}{\sum X^{2}}\)
4. Substitute a and b into
\(Y=a+bX\)
\(a\)
\(b\)
QUESTION 12 OF 20
An economic plan requires the total planned output over 4 years. If the planned output index is given by:
\(y=50x\)
find the total output represented by:
\(\int_{0}^{4}\,50xβdx\)
QUESTION 13 OF 20
Which of the following is an incorrect statement regarding the time-reversal test for index numbers?
\(I_{01}\times I_{10}=1\)
QUESTION 14 OF 20
Consider the cost of living indices for two places:
β’ Place A:
\(y=120\)
β’ Place B:
\(y=110+2x\)
Find the value of x (in years) at which the index of Place B intersects and begins to exceed that of Place A.
QUESTION 15 OF 20
The rate of change of a poverty index is given by:
\(\frac{dI}{dt}=-2t\)
with initial condition
\(I(0)=150\)
Using integration, find the value of the poverty index at t = 5.
Given:
\(I(t)=150-t^{2}\)
QUESTION 16 OF 20
Why are index numbers increasingly used in the social sphere?
QUESTION 17 OF 20
Using the method of least squares for 6 observations (n = 6), given:
\(\sum Y=35.6,Β \sum XY=9.2,Β \sum X^{2}=70\)
Find the value of constant a in the trend line:
QUESTION 18 OF 20
Given:
\(\vec{Q_{0}}=100\hat{i}+50\hat{j}\)
\(\vec{P_{n}}=3.8\hat{i}+45\hat{j}\)
The dot product
\(\vec{P_{n}}β
\vec{Q_{0}}\)
gives:
QUESTION 19 OF 20
Policy makers construct 4 index numbers using the following methods:
β’ Simple Aggregate
β’ Laspeyres
β’ Paasche
β’ Fisher
If one index is selected at random, what is the probability that it satisfies the time-reversal test?
QUESTION 20 OF 20
In decision making, moving averages smooth out fluctuations in data.
If the original data oscillates strictly between:
\(y=30\)
and
\(y=50\)
then the 3-year moving average trend line will:
Test Complete!
Answer Review
1 Q1. Concept of Index Number [Integral]
If the marginal change of an index number is modeled continuously over time as:
\(\frac{dI}{dt}=6t\)
and the base period index is given by
\(I(0)=100\)
find the index function
\(I(t)\)
using integration.
Integrate the derivative Add integration constant Apply initial condition
Given: \(\frac{dI}{dt}=6t\) Integrating both sides: \(I(t)=\int 6tβdt=3t^{2}+C\) Using initial condition: \(I(0)=100\) So, \(100=3(0)^{2}+C\) Thus: \(C=100\) Final equation: \(I(t)=100+3t^{2}\) Hence, Option B is correct.
- Option A β Ignores the initial condition.
- Option C β Incorrect integration of 6t.
- Option D β Integral of 6t is not tΒ³.
Used
- Substitution
Application:
- Integrate and apply the initial value directly.
Final Logic:
- Correct integration plus constant gives the required function.
"Integrate β Add Constant"
2 Q2. Index as Measure of Change [Vector-Based Numerical]
Consider prices represented as a position vector:
\(\vec{r}=P_{0}\hat{i}+P_{n}\hat{j}\)
Given:
\(\vec{r}=30\hat{i}+46\hat{j}\)
representing wheat prices in 1997 and 2001 respectively, the price relative index is defined as:
\(\left(\frac{y-component}{x-component}\right)\times 100\)
Find the value of the index number.
Use relative index formula Divide current by base price Multiply by 100
Given: \(P_{0}=30,Β P_{n}=46\) Index number: \(\frac{46}{30}\times 100\) Calculating: \(153.33\) Hence, Option C is correct.
- Option A β Incorrect division.
- Option B β Miscalculated ratio.
- Option D β Overestimated value.
Used
- Substitution
Application:
- Substitute vector components into the index formula.
Final Logic:
- Relative price increase equals 153.33.
"Current Γ· Base Γ 100"
3 Q3. Relative Comparison Idea [Case/Numerical]
A departmental store spent βΉ1.3 lakh in 1990 and βΉ2.9 lakh in 2000 on newspaper advertisements. Using 1990 as the base year, find the price index for advertisement prices in 2000.
\(Index=\left(\frac{2.9}{1.3}\right)\times 100\)
Divide current by base Multiply by 100 Round appropriately
Applying the index formula: \(\frac{2.9}{1.3}\times 100\) Calculation: \(223.08\approx 223\) Therefore, Option D is correct.
- Option A β Too low compared to actual ratio.
- Option B β Incorrect computation.
- Option C β Assumes doubling only.
Used
- Substitution
Application:
- Use the standard index number formula directly.
Final Logic:
- Advertisement expenditure index equals 223.
"Relative Rise Γ 100"
4 Q4. Base and Current Period [Probability]
Out of 5 available years (2000, 2001, 2002, 2003, 2004), a statistician randomly selects one year as the base period and one strictly subsequent year as the current period.
What is the probability that 2000 is chosen as the base period?
\(TotalΒ possibleΒ pairs=\left(\frac{5}{2}\right)=10\)
\(FavourableΒ cases=4\)
\(P=\frac{4}{10}\)
Count total valid pairs Count favorable outcomes Use probability formula
Possible current years after 2000 are: 2001, 2002, 2003, 2004 Thus favorable cases = 4. Total ordered valid pairs: \(\left(\frac{5}{2}\right)=10\) Therefore: \(P=\frac{4}{10}\) Hence, Option A is correct.
- Option B β Incorrect favorable count.
- Option C β Overestimated probability.
- Option D β Incorrect denominator.
Used
- Substitution
Application:
- Apply probability = favorable/total.
Final Logic:
- Probability equals 4/10.
"Probability = Favorable Γ· Total"
5 Q5. Meaning of Index Series [Moving Average/Data]
For a 4-year moving average analysis, the 4-year moving totals are:
1730 and 1772
Find the centered total for these periods:
Add adjacent totals Divide by 2 Center the moving totals
Centered total: \(\frac{1730+1772}{2}\) Calculating: \(\frac{3502}{2}=1751\) Thus, Option A is correct.
- Option B β Divides twice unnecessarily.
- Option C β Incorrect averaging.
- Option D β Wrong arithmetic.
Used
- Substitution
Application:
- Compute centered moving total directly.
Final Logic:
- Centered value equals 1751.
"Centered = Average of Adjacent Totals"
6 Match List I with List II based on index number formulae.
| List I | List II |
|---|---|
| 1. Simple Aggregative | a. (Ξ£PnQn / Ξ£P0Qn) Γ 100 |
| 2. Simple Average of Relatives | b. (Ξ£Pn / Ξ£P0) Γ 100 |
| 3. Laspeyres' Index | c. (Ξ£PnQ0 / Ξ£P0Q0) Γ 100 |
| 4. Paasche's Index | d. [Ξ£((Pn / P0) Γ 100)] / N |
Identify formulas carefully Laspeyres uses base weights Paasche uses current weights
Mappings: β’ Simple Aggregative β \(\frac{\sum P_{n}}{\sum P_{0}}\times 100\) β’ Simple Average of Relatives β \(\frac{\sum \left(\frac{P_{n}}{P_{0}},\ 100\right)}{N}\) β’ Laspeyres β base-period weights: \(\frac{\sum P_{n}Q_{0}}{\sum P_{0}Q_{0}}\times 100\) β’ Paasche β current-period weights: \(\frac{\sum P_{n}Q_{n}}{\sum P_{0}Q_{n}}\times 100\) Hence, Option C is correct.
- Option A β Incorrectly swaps formulas.
- Option B β Misplaces Laspeyres and Paasche.
- Option D β Wrong matching structure.
Used
- Option Grouping
Application:
- Group formulas based on weight usage.
Final Logic:
- Base weights β Laspeyres; current weights β Paasche.
"L = Old Weights, P = Present Weights"
7 Q7. CPI and GDP Indices [Multiple Correct]
Which of the following statements regarding Consumer Price Index (CPI) and GDP are correct?
(i) They are expressed as pure numbers.
(ii) They rely on absolute non-relative metrics.
(iii) They measure changes in general economic variables over time.
Index numbers are relative measures Expressed as pure numbers Used for economic comparisons
CPI and GDP indices are relative measures expressed as pure numbers or percentages. They measure economic changes over time. Statement (ii) is incorrect because index numbers are based on relative comparison, not absolute values. Thus, statements (i) and (iii) are correct.
- Option A β Includes incorrect statement (ii).
- Option B β Statement (ii) is false.
- Option C β Ignores statement (iii).
Used
- Elimination
Application:
- Remove options containing false statement (ii).
Final Logic:
- Only (i) and (iii) remain correct.
"Index = Relative Measure"
8
Nifty belongs to NSE Sensex belongs to BSE Both track stock market movement
Nifty and Sensex are stock market indices. They are used to monitor movements in the National Stock Exchange (NSE) and Bombay Stock Exchange (BSE). Therefore, Option A is correct.
- Option B β Unrelated to stock indices.
- Option C β Retail sales use separate indices.
- Option D β GDP is measured differently.
Used
- Contextual/Tonal Matching
Application:
- Use stock market context from the passage.
Final Logic:
- Nifty and Sensex belong to NSE and BSE.
"NiftyβNSE, SensexβBSE"
9
Base year must be normal Avoid abnormal economic conditions Natural calamities distort prices
An ideal base year should reflect normal economic conditions. Years with booms, depressions, or natural calamities distort comparisons and are avoided. Hence, Option B is correct.
- Option A β Normal stability is desirable.
- Option C β Average fluctuations are acceptable.
- Option D β Standard of living changes are measured, not avoided.
Used
- Extreme Word Filter
Application:
- Identify abnormal conditions mentioned in the passage.
Final Logic:
- Abnormal years are unsuitable as base years.
"Base Year = Normal Year"
10 Q10. Living Standard Measure [AssertionβReason]
Assertion (A): The Laspeyres index may overestimate the rise in the cost of living.
Reason (R): The Laspeyres index uses base-period weights, ignoring the possibility that consumers may reduce consumption of items that become relatively more expensive.
Laspeyres uses old weights Consumer substitution ignored Cost rise may be overstated
The Laspeyres Index uses base-year quantities as weights. Consumers often reduce consumption of goods that become expensive, but Laspeyres ignores this substitution effect. Therefore, it may overestimate the increase in cost of living. Hence, both Assertion and Reason are true, and the Reason correctly explains the Assertion.
- Option A β Both statements are actually true.
- Option B β Reason is also true.
- Option D β Assertion is true.
Used
- Contextual/Tonal Matching
Application:
- Link the substitution effect with Laspeyres bias.
Final Logic:
- Base weights cause overestimation.
"Laspeyres Uses Old Habits"
11 Arrange the steps involved in forecasting using the method of least squares for fitting a straight line:
\(Y_{t}=a+bX\)
1. Compute
\(a=\frac{\sum Y}{n}\)
2. Set the midpoint of time as origin so that
\(\sum X=0\)
3. Compute
\(b=\frac{\sum XY}{\sum X^{2}}\)
4. Substitute a and b into
\(Y=a+bX\)
\(a\)
\(b\)
Start by setting origin Then compute constants Finally substitute into trend equation
In the least squares method: 1. First set the midpoint as origin so that \(\sum X=0\) 1. Then calculate \(a=\frac{\sum Y}{n}\) 1. Next calculate slope: \(b=\frac{\sum XY}{\sum X^{2}}\) 1. Finally substitute into: \(Y=a+bX\) \(a\) \(b\) Thus, the correct order is 2, 1, 3, 4.
- Option A β Midpoint origin must be set before calculations.
- Option B β Substitution cannot occur before finding constants.
- Option C β Sequence is logically incorrect.
Used
- Contextual/Tonal Matching
Application:
- Arrange steps according to the standard forecasting procedure.
Final Logic:
- Constants are computed only after defining the origin.
"Origin β a β b β Equation"
12 An economic plan requires the total planned output over 4 years. If the planned output index is given by:
\(y=50x\)
find the total output represented by:
\(\int_{0}^{4}\,50xβdx\)
Integrate the function Apply upper and lower limits Definite integral gives total output
Integrating: \(\int 50xβdx=25x^{2}\) Applying limits: \(25(4)^{2}-25(0)^{2}\) Thus: \(25\times 16=400\) Therefore, Option A is correct.
- Option B β Incorrect integration.
- Option C β Overestimation.
- Option D β Arithmetic error.
Used
- Substitution
Application:
- Apply definite integration directly.
Final Logic:
- Area under the output curve equals 400.
"Integral = Total Accumulation"
13 Which of the following is an incorrect statement regarding the time-reversal test for index numbers?
\(I_{01}\times I_{10}=1\)
Fisher satisfies the test Laspeyres does not satisfy it Reciprocal condition defines the test
The time-reversal test requires: \(I_{01}\times I_{10}=1\) Fisher's Ideal Index satisfies this property. Laspeyres and Paasche indices do not satisfy the time-reversal test. Hence, Option B is the incorrect statement.
- Option A β Fisher's Ideal Index correctly satisfies the test.
- Option C β This is the exact mathematical condition.
- Option D β Paasche indeed fails the test.
Used
- Elimination
Application:
- Identify which statement contradicts standard index theory.
Final Logic:
- Only Fisher satisfies the time-reversal test.
"Fisher Passes Time Test"
14 Consider the cost of living indices for two places:
β’ Place A:
\(y=120\)
β’ Place B:
\(y=110+2x\)
Find the value of x (in years) at which the index of Place B intersects and begins to exceed that of Place A.
Equate both indices Solve linear equation Intersection gives threshold year
At intersection: \(110+2x=120\) Solving: \(2x=10\) Thus: \(x=5\) Hence, Option C is correct.
- Option A β Gives value below 120.
- Option B β Still below intersection.
- Option D β Occurs after the intersection point.
Used
- Substitution
Application:
- Equate both linear equations.
Final Logic:
- Equality occurs at x = 5.
"Intersection β Equal Values"
15 The rate of change of a poverty index is given by:
\(\frac{dI}{dt}=-2t\)
with initial condition
\(I(0)=150\)
Using integration, find the value of the poverty index at t = 5.
Given:
\(I(t)=150-t^{2}\)
Integrate rate equation Use initial condition Substitute t = 5
Integrating: \(I(t)=150-t^{2}\) At t = 5: \(I(5)=150-25\) Thus: \(I(5)=125\) Therefore, Option D is correct.
- Option A β Incorrect substitution.
- Option B β Arithmetic mistake.
- Option C β Miscalculated square value.
Used
- Substitution
Application:
- Substitute the given value directly into the function.
Final Logic:
- Poverty index at t = 5 equals 125.
"150 β 25 = 125"
16 Why are index numbers increasingly used in the social sphere?
Index numbers measure social conditions Prosperity and poverty are composite concepts Used in socio-economic analysis
Index numbers help quantify broad socio-economic measures such as prosperity, poverty, and standards of living. These are composite measures that cannot be expressed directly through a single raw value. Thus, Option A is correct.
- Option B β Global warming calculations use scientific climate models.
- Option C β Vector derivatives are unrelated.
- Option D β Atomic weights are scientific constants.
Used
- Odd One Out
Application:
- Identify the socially relevant application.
Final Logic:
- Only prosperity measurement belongs to social index usage.
"Social Index = Prosperity Measure"
17 Using the method of least squares for 6 observations (n = 6), given:
\(\sum Y=35.6,Β \sum XY=9.2,Β \sum X^{2}=70\)
Find the value of constant a in the trend line:
Use least squares formula Divide total Y by n Obtain intercept a
The formula is: \(a=\frac{\sum Y}{n}\) Substituting: \(a=\frac{35.6}{6}\) Thus: \(a\approx 5.93\) Therefore, Option B is correct.
- Option A β Incorrect division.
- Option C β Overestimation.
- Option D β Arithmetic error.
Used
- Substitution
Application:
- Apply the direct least squares formula.
Final Logic:
- Intercept value equals 5.93.
"a = Total Y Γ· n"
18 Given:
\(\vec{Q_{0}}=100\hat{i}+50\hat{j}\)
\(\vec{P_{n}}=3.8\hat{i}+45\hat{j}\)
The dot product
\(\vec{P_{n}}β
\vec{Q_{0}}\)
gives:
Multiply corresponding components Add the products Dot product gives scalar value
Dot product: \(\left(3.8)(100)+(45)(50\right)\) Calculating: \(380+2250=2630\) Hence, Option C is correct.
- Option A β Ignores one component.
- Option B β Arithmetic error.
- Option D β Overcalculated value.
Used
- Substitution
Application:
- Apply the vector dot product formula.
Final Logic:
- Scalar result equals 2630.
"Dot Product = Multiply & Add"
19 Policy makers construct 4 index numbers using the following methods:
β’ Simple Aggregate
β’ Laspeyres
β’ Paasche
β’ Fisher
If one index is selected at random, what is the probability that it satisfies the time-reversal test?
Only Fisher satisfies the test Total methods = 4 Probability = favorable/total
Among the four methods listed, only Fisher's Ideal Index satisfies the time-reversal test. Thus: \(P=\frac{1}{4}=0.25\) Therefore, Option D is correct.
- Option A β Not all methods satisfy the test.
- Option B β More than one method does not qualify.
- Option C β Exactly half do not satisfy it.
Used
- Elimination
Application:
- Identify the only valid method.
Final Logic:
- One successful case out of four.
"Only Fisher Passes"
20 In decision making, moving averages smooth out fluctuations in data.
If the original data oscillates strictly between:
\(y=30\)
and
\(y=50\)
then the 3-year moving average trend line will:
Moving averages smooth data Average stays within bounds Extremes are reduced
A moving average is computed from nearby observations. If all observations lie between 30 and 50, then their averages must also remain within that interval. Thus, the trend line cannot exceed 50 or fall below 30. Therefore, Option A is correct.
- Option B β Averages cannot exceed the maximum value.
- Option C β Averages cannot fall below the minimum value.
- Option D β Moving averages are smoother, not necessarily constant.
Used
- Elimination
Application:
- Remove impossible average behaviors.
Final Logic:
- Average values remain bounded by original data limits.
"Average Stays Within Limits"
