Age Structure

The governing concept is the conversion of a youthful age structure into productive human capital. A large young population can later enlarge the working-age group, but education, training and labour-market opportunities determine whether that group is skilled and employed. If schooling is weak, many young people may enter adulthood without literacy, technical competence or adaptable skills. The resulting low productivity, unemployment and underemployment can create fiscal and social pressures instead of a demographic dividend. Option A captures this risk. Option C is incorrect because skills do not arise automatically with age. Option B is not the central issue, and option D is false because population structure strongly influences labour supply and economic planning.

The governing concept is the relationship between a group’s share and the total population. Initially, the elderly number equals 12 percent of the original total. Later, the total population is larger and the elderly share is 18 percent. Since both the base population and the proportion applied to it have increased, the absolute elderly population must be larger. For example, 12 percent of 100 is 12, whereas 18 percent of even 110 is 19.8. Option A is therefore certain. The other options make claims not supported by the data: children need not disappear, the working-age group need not halve, and the birth rate need not double.

The governing concept is the dependency ratio, calculated as the dependent population divided by the working-age population, multiplied by 100. Children aged 0–14 and older people aged 60 and above are counted as dependents here, so the dependent share is 20 + 15 = 35 percent. The working-age share is 65 percent. Therefore, total dependency ratio = (35 ÷ 65) × 100 = 53.846..., approximately 54 dependents per 100 working-age people. Option A is correct. Option B confuses the dependent percentage of the total population with the ratio per 100 workers. Options C and D do not follow from the given formula or percentages.

The governing concept is the difference between demographic potential and realised economic development. A declining total dependency ratio generally means that dependents form a smaller share relative to the working-age population. This may result from falling child dependency, a larger working-age share or other age-structure changes, and it can create an opportunity for a demographic dividend. However, prosperity is not guaranteed. The country still needs jobs, education, health, productivity, infrastructure, effective governance and fair participation to convert the opportunity into higher living standards. Therefore option A is the conclusion that cannot always be drawn. Options B and D are reasonable possibilities, while C can occur when fertility and the child share decline.

The governing concept is age structure: the average age of a population rises when the proportional weight of older groups increases relative to younger groups. A decline in fertility produces smaller child cohorts, while improved survival and longer life expectancy allow more people to reach old age. Together, these changes increase the mean or average age. Therefore, option A is correct. Option B is unlikely because persistently high fertility creates a broad base of children and usually keeps the average age low. Option C would make the population younger, not older. Option D cannot generally create population ageing because an inflow made up only of newborns would enlarge the youngest group. The conclusion concerns relative age shares, not merely the total number of people.

The governing concept is population momentum, which arises from the existing age composition rather than from fertility alone. If a country previously had high fertility, it may contain a very large group of children and adolescents. As this group reaches reproductive ages, the number of potential parents becomes large. Consequently, even if the average number of births per woman declines, the total number of births can remain substantial for several years or decades. Option A is therefore correct. Option B is false because a lower birth rate does not itself produce more births. Option C is biologically impossible, and option D ignores the major influence of age structure on future growth. The timing and size of earlier cohorts are therefore essential to understanding population change.

The governing concept is that age structure depends on fertility, mortality, survival and migration, not on fertility alone. When country A has higher life expectancy, a larger fraction of its population is likely to survive into older age groups. Over time, this can raise the proportion of elderly people, even though the fertility rates of the two countries are identical. Option A is therefore the most reasonable conclusion. Option C is incorrect because equal fertility does not guarantee equal mortality or survival patterns. Option B contradicts the meaning of higher life expectancy, while option D is impossible because a population contains several age groups. The result is a likely tendency, not an absolute prediction, since migration and other demographic conditions may also influence the final structure.

The governing concept is the dependency ratio, which compares the dependent population with the working-age population rather than with the entire population. The formula is: dependency ratio = (dependents ÷ working-age population) × 100. Substituting the given shares gives (45 ÷ 55) × 100 = 81.818..., which rounds to approximately 82 dependents per 100 working-age persons. Thus, option A is correct. Option B incorrectly uses the dependent percentage in the total population as though it were the ratio per 100 workers. Option C is the working-age share, not the calculated ratio, and option D results from using the wrong relationship or denominator. Identifying the base population before calculation prevents this common error.

The traditional dependency ratio is an age-based indicator. It usually places children and older persons in a dependent category and compares their number with the working-age population. Its limitation is that chronological age does not always equal economic dependence. Many older people remain healthy, employed, self-employed, unpaid family workers or financially independent, especially when healthy life expectancy and retirement ages increase. Therefore, option A is correct: the measure may oversimplify actual participation and support needs. Option B is false because children are normally counted as dependents, not workers. Option C is irrelevant because the ratio can be calculated from population counts, and option D is false because the indicator is not a migration measure. Employment and health data provide a more realistic complement.

The governing concept is cohort movement through the age structure. A long period of high fertility creates unusually large groups of children and young people. When fertility then falls sharply, the newly born cohorts become smaller, so the child share and the base of the age pyramid begin to narrow. Meanwhile, the large cohorts born earlier advance into working ages during the following years and decades. Thus, option A correctly describes the likely transition. Option D is opposite to the expected effect of falling fertility. Options B and C are also impossible because demographic groups do not disappear instantly; they age gradually. This transition may create a demographic dividend, but only if education, health, skills and employment opportunities can absorb the expanding working-age population.

The governing concept is the relationship between age composition and labour supply. As population ageing increases, the proportion of older people rises while the number of younger entrants may become smaller. Retirements can then exceed the number of new workers entering some occupations, producing labour shortages, skill gaps and greater pressure on pension and care systems. Option A is correct because governments and employers may respond through later retirement, retraining, productivity improvements, higher female participation or carefully managed migration. Option B is unacceptable and unrelated to a sound demographic response. Option C is too extreme: ageing changes the supply and composition of labour but does not eliminate all employment. Option D is also wrong because working-age analysis remains important for planning.

The governing principle is that the percentages of all age groups together must total 100 percent. If the proportions of children and elderly people are both small, their combined share occupies only a limited part of the population. The remaining and therefore relatively larger share must belong mainly to the middle or working-age population. Hence, option A is correct. Option B cannot be inferred because newborns are only one small part of the child group. Option C contradicts the statement that the elderly share is low. Option D is impossible because every person must belong to some age category. Such a structure may result in a low dependency ratio and can provide a demographic opportunity, but the economic benefit depends on education, health, skills and the availability of productive employment.

The governing concept is the complement of population shares and the distinction between percentage points and percentage change. Initially, the working-age share was 100 − 35 − 8 = 57 percent. In the later period, it was 100 − 22 − 13 = 65 percent. The change is therefore 65 − 57 = 8 percentage points, so option A is correct. Option C incorrectly treats the entire 13-point fall in the child share as an equal rise in the working-age share, ignoring that the elderly share increased by 5 points. Option B has the wrong direction and value, while option D ignores the changed composition. The answer is expressed in percentage points because two population shares are being subtracted directly.

The governing concept is the youth dependency ratio, calculated as the population of children divided by the working-age population and multiplied by 100. This ratio becomes high when there are many children for each person of working age. Therefore, option A is correct: a very large child share combined with a relatively small working-age group produces the largest numerator-to-denominator relationship. Option B describes a situation more likely to increase old-age dependency, not youth dependency. Option C has the opposite structure, with many potential workers and few children. Option D removes children from the dependent category by placing them in working ages, so it cannot represent high youth dependency. A high ratio may increase demands for schooling, health care and child nutrition.

The governing concept is age structure: the width of each horizontal bar represents the relative size of a particular age group. Ages 25 to 39 are mainly young-adult and working ages. A concentrated bulge in this section, with narrower groups immediately below and above it, is most plausibly produced when people in these ages move into the country for employment, education, marriage, or other opportunities. This is age-selective in-migration. High infant mortality would reduce the youngest bars, elderly in-migration would widen older bars, and fertility becoming zero would affect younger cohorts rather than create a young-adult bulge. Therefore, option C is correct.

The governing concept is the demographic dividend. A large working-age share creates a potential advantage because more people could produce goods, earn income, and support dependents. It does not guarantee those outcomes. When labor-force participation is very low, many working-age people are outside employment or active job seeking, so the potential labor supply is not converted into actual production, tax revenue, or household income. Education, health, skills, gender access, suitable jobs, and institutions also influence the result. Option A is too absolute, option C is not necessarily true, and option D wrongly denies the relevance of age structure. Therefore, B is correct.

Total dependency is based on the combined number of children and older persons relative to the working-age population. If elderly dependency rises by exactly the amount that child dependency falls, the sum of the two dependent groups remains approximately unchanged, assuming the denominator is also stable or the question is comparing equivalent shares. For example, a six-point rise in elderly dependency offset by a six-point fall in child dependency leaves the total unchanged. The composition of dependency still changes: demand for schools may decline while demand for pensions and elder-care services grows. Thus option B is correct.

The governing concept is age-selective migration and its effect on dependency. Young adults usually belong to the working-age population. When many of them leave the origin region, the denominator used for elderly dependency becomes smaller, while the number of elderly residents may remain nearly unchanged. Consequently, the number of older persons per working-age person can rise, even without any immediate increase in the elderly population. Out-migration may also reduce future births if migrants are of reproductive age, but it cannot make child dependency automatically zero. The working-age group declines rather than increases. Therefore, option B is the best answer.

Total dependency is the combined burden of child dependency and elderly dependency relative to the working-age population. If the child component is very small but the total remains very high, the elderly component must be contributing a large share of the total. This pattern is typical of an ageing population in which fertility has remained low for a long period and survival to older ages is substantial. A very large working-age population would generally enlarge the denominator and tend to lower dependency, while a large child population contradicts the stated low child dependency. Therefore, option B is the only logical explanation.

The governing concept is age structure and its movement through time. A very broad middle means that a large share of the population is currently in or approaching working ages. If education, health, skills and employment are adequate, this concentration can produce a demographic dividend because more workers support relatively fewer children. The gradually narrowing base means that recent birth cohorts are smaller. As the large middle-aged cohorts grow older and smaller cohorts replace them, the labour force may eventually decline and old-age dependency may rise. Thus option A correctly combines the near-term opportunity with the long-term challenge. Option B reverses the likely dependency pattern, while C and D contradict the pyramid evidence.

The governing idea is cohort comparison in a population pyramid. The 10–19 group was born roughly one to two decades earlier than the youngest children. If that adolescent band is wider than the base, those earlier birth cohorts were larger than the more recent cohorts. The base can still be broad, showing that the child population remains substantial, but its relative narrowing suggests that fertility has declined somewhat in recent years. Therefore option B is the most appropriate conclusion. Option A would be more plausible if the youngest cohorts were wider than the adolescent group. Option C is unrelated to the stated age bands, and option D is too absolute because migration alone cannot be inferred from this shape.

The governing concept is the distinction between demographic dependency and economic dependency. An age-based dependency ratio classifies people above a selected age threshold as dependents, usually because many are outside the labour force. It does not normally check whether each older person actually works, earns income, or receives support. If a large proportion of the elderly remain economically active, the age-based measure counts them as dependents even though they may support themselves and contribute to production or taxes. It can therefore overstate the real economic burden. Option B is correct. The other choices confuse counting, age categories, or the arithmetic meaning of a ratio.

The governing concept is that the economic effect of ageing depends not only on the number of older people but also on the resources generated by workers. A rising elderly share can increase spending on pensions, health care and support services. Rapid productivity growth, however, means that each worker may produce more goods, services and income. The additional output can help finance support for older people and partly offset the pressure created by ageing. It does not remove older people, reverse the age structure, or make the age-based dependency ratio zero. Therefore option B is the balanced conclusion. The other choices confuse economic mitigation with demographic reversal.

The governing concept is cohort progression through the age structure. Very low fertility produces small birth cohorts in the present. After roughly 15–20 years, those same small cohorts reach adolescence and begin entering working ages, so the flow of new labour-market entrants will be smaller. If earlier, larger cohorts are also ageing, the country may later experience labour shortages and greater elderly dependency. Low fertility does not automatically reduce the number of older people, double the working-age population, or cause child dependency to rise. Therefore option A is the only conclusion that follows directly from the demographic timing. The exact outcome can also depend on migration and mortality, but the cohort effect remains clear.

The total dependency ratio compares dependent age groups, usually children and older people, with the working-age population. A low ratio means that the age structure offers a potentially favorable balance: relatively many people are in the working ages and relatively fewer are dependent. This condition can support a demographic dividend, but it is only an opportunity, not an automatic result.

Very high unemployment shows that many working-age people are not being productively absorbed into the economy. Without jobs, education, skills, health, infrastructure, and effective policies, the potential advantage may remain unused. Unemployment can also create financial and social pressures despite the favorable age structure. Therefore, the best conclusion is B: the age structure is favorable, but it is not fully producing economic gains. A is too certain, while C and D do not follow from a low dependency ratio.