Q.Statements that are incorrect in relation to index numbers -
Index number is a geographical tool.
Index numbers measure changes in the air pressure.
Index numbers measure relative changes in economic variable.
Index numbers are specialized averages.

Odd word = Selection Index Number.

Index numbers are classified into these standard types:

• Price index number — measures changes in the general price level.
• Quantity index number — measures changes in the volume of goods produced or consumed. …

The incorrect statements about index numbers are (a) and (b), so the answer is a, b.

An index number is a statistical device that measures relative changes in an economic variable (such as prices or output) over time. Judging each statement:

• (a) 'Index number is a geographical tool' — incorrect; it is a statistical tool, not a geographical one. …

The correct answer is to measure the general changes in the prices of goods.

A price index number is a statistical measure that shows the average change in the prices of a group of goods and services between a base year and a current year, expressed as a percentage of the base. It captures the general movement of prices (rise or fall) rather than the price of a single item, and is widely used to study inflation and the cost of living. The other option …

The odd word is Laspeyre's Price Index Number — it is a weighted index number, while price, quantity and value index numbers are the ordinary (simple) types.

Index numbers can be classified by method of construction (simple/unweighted vs weighted) and by content (price, quantity, value):

• Price Index Number — measures change in price levels.
• Quantity Index Number — measures change in physical volume of goods.
• Value Index Number — measures change in total value (price × quantity). …

The correct option is Assertion (A) is false but Reasoning (R) is true.

An index number measures the relative change in a group of related variables (like prices) over time. It is constructed from a sample of representative items, not from every single commodity or factor in the economy — so reasoning (R) is true. Precisely because it rests on samples, an index number does not consider all factors; it gives only an a …