JAMB Economics 2010 Past Questions & Answers

The most widely accepted definition of economics, by Lionel Robbins, describes it as the study of human behaviour in relation to ends and scarce means which have alternative uses. This means economics is fundamentally about how we manage our limited resources (scarcity) to satisfy our unlimited wants by making choices. 'Efficient allocation of resources' is the modern way of describing this process of managing scarcity and making the best choices.

Common mistake: Students may be tempted to choose 'production of goods' because it is a key economic activity, but this is too narrow as economics also studies consumption, services, and distribution.

This question is about the mobility of labour, which is a factor of production. Horizontal mobility occurs when a worker moves between jobs but remains in the same industry or profession. Since both a classroom teacher and a principal work within the education sector, the change is seen as a horizontal movement to a different role within the same professional field.

Common mistake: Students may incorrectly choose 'vertical mobility' because a promotion involves a higher rank, but in this context, the key is that the individual has not changed their industry, which is the definition of horizontal mobility being tested.

The stock market is a key financial institution where the prices of shares are determined by the forces of demand and supply. A downturn in prices shows that the market is working to regulate itself; it is a reaction to new information or changing investor confidence, causing prices to adjust downwards to a new equilibrium. This self-correcting mechanism is a core regulatory feature of a free market.

Common mistake: Students often confuse this with 'the invisible hand', which is a broader concept about how self-interest benefits society, whereas 'the regulatory nature' specifically points to the market's internal mechanism for price correction.

In statistics, the formula to calculate the mean (average), represented by X, is X = Σfx / N. Here, Σfx is the sum of the products of the values and their frequencies, and N is the total number of items. The question asks for the value of Σfx. To find it, we rearrange the formula to be Σfx = X * N. Given that X = 6 and N = 6, we can calculate Σfx as 6 * 6, which equals 36.

Common mistake: A common mistake is to add the values of X and N $(6 + 6 = 12)$ instead of multiplying them, which is the correct operation according to the rearranged formula for the mean.

Standard deviation is a statistical tool used to measure how spread out a set of data is from its average (mean). A large standard deviation means the data points are far from the average, while a small one means they are clustered closely around the average. This spread or 'scatter' of data is known as dispersion, so standard deviation is a primary measure of dispersion.

Common mistake: Students often confuse measures of dispersion with measures of central tendency, leading them to wrongly select option C, thinking standard deviation is a type of average rather than a measure of spread around an average.

The mean is the average of a set of numbers, calculated by summing all the values and dividing by the count of those values. This process gives equal weight to every value, making the mean the 'center of gravity' or balancing point for the entire dataset. It is the point where the sum of the distances of all data points from it is zero, perfectly balancing the observations.

Common mistake: Students often mistakenly choose option C, confusing the mean (the average) with the median (the middle value in an ordered dataset).

The mode is a measure of central tendency that identifies the value that appears most frequently in a dataset. The term 'most popular' directly means the one that occurs most often. Therefore, to find the most popular shoe or dress size, you would find the mode of the sales data, which is the size sold most frequently.

Common mistake: Students might mistakenly choose the mean or median because they are also common measures of average, but 'most popular' specifically refers to the most frequent item, which is the mode.

The rule for tax burden is that the side of the market that is less elastic (less responsive to price changes) will bear a greater share of the tax. In this question, demand is more elastic than supply, which means supply is less elastic. Therefore, producers, who are on the supply side, cannot easily adjust their output and will be forced to absorb a larger portion of the tax.

Common mistake: Students often mistakenly believe that the more elastic side of the market bears the greater tax burden, when in fact it is the less elastic (more inelastic) side that cannot easily escape the tax.

Elastic demand means that consumers are very sensitive to changes in price. If the price increases, the quantity demanded will decrease by a larger percentage. Because the drop in the quantity sold is much greater than the rise in price, the producer's total revenue (Price x Quantity) will fall.

Common mistake: Students might mistakenly choose 'increase' because they have a general intuition that a higher price leads to more money, without considering the significant drop in quantity demanded that occurs with elastic goods.

Excess demand, also known as a shortage, occurs when the price of a good is below its equilibrium price. According to the law of demand, a decrease in the price of beans will cause consumers to want to buy more. At the same time, the law of supply states that sellers will be willing to sell less at a lower price, creating a situation where the quantity demanded is greater than the quantity supplied.

Common mistake: Students often confuse excess demand with excess supply, which is actually caused by an increase in price above the equilibrium level.