Economics 2017 Jamb Examination

Farmers often face unstable income because their output depends heavily on biological factors. Diseases and pests can destroy crops or reduce yield significantly, creating major fluctuations in earnings.
Since most Nigerian farmers rely on small-scale production and lack access to modern inputs, they are more vulnerable to crop failures caused by pests and diseases, making option A the most consistent and economically sound reason.

Tax revenue is a compulsory levy imposed by the government on individuals and organisations. It is unique to government because no private entity possesses the legal authority to collect taxes.
Other sources listed can be earned by private individuals or firms, but taxation is exclusively a governmental function, making it uniquely tied to public income generation.

Price control occurs when the government sets maximum or minimum prices for essential goods in order to protect consumers or producers. This typically applies to basic commodities such as fuel, food items, and medicine.
It prevents exploitative pricing and ensures affordability, which aligns directly with the description in the question.

The price system coordinates how resources are allocated by signalling producers on what to produce and consumers on what to buy. Through the interaction of demand and supply, production and consumption are regulated automatically without central planning.
This regulatory function makes option D the most accurate description of the price system.

Reducing export duties makes a country’s goods more competitive in the global market by lowering their cost. This can lead to an increase in export volume and improve the ratio between export prices and import prices, thereby improving terms of trade.
Other options do not directly enhance a country’s trade position as clearly as lowering export duties.

Form utility is created when the physical composition or structure of a good is altered to make it more useful to the consumer. Manufacturing processes such as turning crude oil into petrol or timber into furniture exemplify form utility creation.
This makes option B the correct classification.

Economic growth indicators measure increases in productive capacity or economic output. GDP, CPI, and PPI reflect economic activity and price changes, but high unemployment reflects economic weakness rather than growth.
Since unemployment signals underutilisation of labour resources, it does not qualify as a growth indicator.

Perfect markets are characterised by many buyers and sellers such that no single entity can influence market price. Imperfect markets have fewer participants, allowing some to exert control.
Thus, the number of sellers and buyers is a fundamental distinction between the two market structures.

The “how” question in economics addresses the method of production—how labour, capital, land, and entrepreneurship should be combined efficiently to produce goods and services.
This focuses on the best production technique, making option B the correct interpretation.

The arithmetic mean for grouped or weighted data is computed as:\[ \text{Mean} = \dfrac{\sum fx}{N} \]Substituting the values:\[ \text{Mean} = \dfrac{340}{20} = 17 \]This gives an average value of 17, making option B correct.