Population Growth

Very rapid population growth means that many additional people must be supported within a short time. Their needs include food, water, housing, education, health care, transport, energy and employment. If infrastructure and public services do not expand as quickly as the population, existing facilities may become crowded and pressure on resources may increase.

Therefore option A is correct: pressure may increase. This is a general possibility, not an unavoidable result in every situation, because planning, technology and investment can improve capacity. The other choices are incorrect because resources do not automatically grow, demand for schools and hospitals usually does not fall, and density depends on both population and area.

A persistently very low birth rate means that relatively few children enter the population each year. Over time, younger age groups become smaller compared with older groups. If older generations continue to survive, the share of people in the elderly category rises, even if the absolute number of elderly people changes slowly.

This process is called population ageing and can increase the demand for healthcare, pensions, and support services. It does not make the death rate zero, nor does it create very high natural increase. Population cannot double every year merely because births are low. Therefore option B is correct: the proportion of the elderly population may increase when a very low birth rate continues for a long time.

Population explosion describes an exceptionally rapid rise in population over a period of time. Such growth can occur when birth rates remain high while death rates fall, or when both natural increase and other population changes produce fast expansion. Rapid growth may increase demand for food, housing, education, health care, employment, water, and other services, although the term mainly refers to the speed of growth.

Therefore, option C, extremely rapid population growth, is correct. A stable population has little or no overall increase, while negative growth means the population is declining. Very slow growth is the opposite of an explosion. The phrase is not a precise calculation by itself; it is a descriptive expression for unusually fast population increase in a particular context.

The direction of population change is most directly shown by the sign of the growth rate. A positive growth rate means that births and other additions exceed deaths and losses, so population increases. A negative rate means that losses exceed additions, so population decreases. A zero rate means there is no net change during the measured period.

The country's size, average elevation, and rainfall may influence population distribution or living conditions, but none of them directly tells whether population is growing or declining. Therefore option D is correct. The sign alone identifies the direction, while the size of the rate indicates how fast the change is occurring. This distinction makes the growth rate the simplest indicator.

The total population changes according to births, deaths, and migration. A falling number of births does not necessarily mean that births are already fewer than deaths plus net out-migration. If the overall balance is still positive, the population can continue increasing, although usually at a slower pace.

Thus option A is the best interpretation: growth continues but may be slowing. The data do not prove that the population is declining, because deaths and migration are not fully specified. They also do not show that deaths have stopped or that migration is zero. More information would be needed to measure the exact growth rate.

Natural increase is the difference between the birth rate and the death rate, without considering migration. If both rates are low and close to one another, only a small excess of births over deaths exists. Consequently, the natural increase is low. A low death rate by itself could support growth, but the birth rate must also be considered.

Here, the question says that both rates are similarly low. Their small difference means the natural increase is likely to be low, so option B is correct. It is not necessarily negative, because births may still be slightly higher than deaths. It is also not very high or automatically doubled; those conclusions are unsupported by the information given.

Answer: C, 20 per thousand. Natural increase is the change in population caused only by births and deaths, without considering migration. Its formula is: natural increase rate = birth rate − death rate. Here, the calculation is 30 per thousand − 10 per thousand = 20 per thousand. This means that, for every thousand people, births exceed deaths by 20. Option A is only the death rate, not the difference between births and deaths. Option B adds the two rates, but deaths must be subtracted because they reduce population. Option D divides 30 by 10, which is not the required operation. Remember: when both birth and death rates are given, subtract deaths from births.

Answer: D, negative 5 per thousand. Natural increase is calculated by subtracting the death rate from the birth rate: natural increase = birth rate − death rate. Therefore, 8 − 13 = −5 per thousand. The negative sign is essential because deaths are greater than births by 5 per thousand. If migration is ignored, this birth-and-death balance would produce a natural decline. Option A gives only the size of the gap and loses its direction. Option B is the sum of the two rates, not the natural increase. Option C simply repeats the birth rate. A useful warning is that natural increase and total population change are not always identical, because migration can increase or decrease the total population.

Answer: A. Population growth shows how the number of people may change in the future. Planners can use this information to estimate requirements for schools, hospitals, housing, drinking water, transport, food, energy and employment. A is correct because it connects population change with future demand for services and resources. B is wrong because national boundaries are not determined by population growth alone. C concerns meteorology, not demography. D concerns soil description, not population planning. A useful memory cue is: people create demand, so changing population requires changing plans.

Population change has two broad components: natural increase, which is births minus deaths, and net migration, which is arrivals minus departures. If births and deaths are equal, natural increase is zero. The city can still grow when more people enter than leave.

This situation is called positive net migration. For example, if 10,000 people arrive and 6,000 leave, the net migration is +4,000, so the city gains 4,000 people even without natural increase. Therefore, option B is correct. High natural increase is not the reason when births and deaths are equal.

Continuous out-migration of young people can reduce population growth in a rural region in two ways. First, the people who leave are removed from the region’s population, so the total may decline directly. Second, when many young adults leave, fewer people remain in the usual childbearing ages, which may reduce the number of births in future years.

As a result, population growth may become slower, zero, or even negative if losses exceed births and other gains. The result is not guaranteed in every case, so option C correctly says it may slow or become negative. Options A and D use absolute claims, while B ignores both the population loss and possible effect on births.

Total population change has two main components: natural increase and net migration. Natural increase is births minus deaths. Net migration is the number entering a country minus the number leaving it. Therefore, a country may have more births than deaths and still experience small growth, no growth, or decline if emigration is large enough.

Option D is correct because total change is found by combining both components: \(\text{Total change} = (\text{Births} - \text{Deaths}) + \text{Net migration}\). Since net migration becomes negative when many people leave, it can offset positive natural increase. Looking only at births, deaths, or area would miss an important part of the population balance. The exact result would require the relevant migration numbers.

Absolute population growth means the actual numerical change in population during a period. It answers the question, “How many people were added or lost?” A growth rate gives a percentage or relative comparison, which is useful for comparing places of different sizes, but it does not by itself show the exact number needing services.

Therefore option A is correct. For planning houses, schools, hospitals, water supply, transport, or jobs, authorities need the actual number of additional people. For example, a small country may have a high percentage growth but add fewer people than a large country with a lower rate. The absolute increase is therefore more useful when the practical number of people must be estimated.

A growth rate is a percentage applied to the starting population. The absolute increase therefore depends on both the rate and the initial population. When two cities have the same rate, the larger starting population produces the larger numerical increase, even though the percentage increase is equal.

For example, at 2% growth, a population of 1 million gains 20000 people, while a population of 10 million gains 200000 people. Thus, the city with the larger initial population may gain more people in absolute terms. Option B is correct. Area is not needed for this comparison, and equal rates do not imply equal numbers added.

Natural increase describes the change produced by births and deaths within a population. It is calculated from the difference between the birth rate and the death rate. A high birth rate adds many people, while a low death rate removes fewer people. Together they create a large positive difference and can produce rapid natural increase.

Therefore the combination of high birth rate and low death rate, option C, is correct. Equal birth and death rates would produce little or no natural increase. Low births with high deaths would usually produce decline. Immigration affects total population growth, but it is migration rather than natural increase, so option D does not answer the question.

Rapid population growth tells us that the total number of people is increasing and that the growth rate is positive. It may also create greater demand for schools, housing, health care, water, transport, and other services, although the size of that demand depends on population structure and planning. However, the statement alone does not identify the exact sources of growth.

Population can rise through natural increase, net in-migration, or a combination of both. Therefore, option D cannot be concluded with certainty: rapid growth need not result only from a high birth rate. Option A follows directly from the meaning of growth, and B is also implied because the rate is positive. C uses “may,” so it is a reasonable possible consequence rather than an absolute claim. The supplied answer is correct and appropriately distinguishes evidence from assumption.

Absolute or complete population increase is the actual number added between two dates. It is not a percentage and it is not the final population. To find it, subtract the initial population from the final population. This simple subtraction distinguishes the increase from the size of the population at the end of the period.

The initial population is 600,000 and the final population is 630,000. Therefore, absolute increase is \(630000-600000=30000\), or 30 thousand people. Option A is correct. The value 630,000 is the final population, not the increase, while 3,000 and 60,000 do not match the subtraction. Percentage growth would require an additional division by the initial population.

Answer: B, a decrease of 30,000. To find population change, subtract the initial population from the final population: 270,000 − 300,000 = −30,000. The negative result shows that the population became smaller. Therefore, the absolute size of the change is 30,000, and its direction is a decrease. Option A has the correct numerical difference but gives the opposite direction. Option C is incorrect because the difference between 300,000 and 270,000 is 30,000, not 3,000. Option D states the final population itself and incorrectly describes it as an increase. A helpful method is: subtract first, then interpret the sign; a negative sign means decline.

Total population changes through two broad components: natural increase and net migration. Natural increase reflects births minus deaths, while net migration reflects immigration minus emigration. If both components are zero, neither births and deaths nor movement across the border produces a net change.

Therefore, the total population remains approximately stable. “Approximately” is appropriate because the statement refers to the balance of the main components and real population records can involve small measurement differences. It will not rapidly grow, decline, or double under the stated conditions. Hence option C is correct.

Natural increase is the difference between the birth rate and the death rate: \(\text{birth rate}-\text{death rate}\). Both rates may fall at the same time, but the important issue is which one falls faster. If the birth rate drops more rapidly than the death rate, the gap between births and deaths becomes smaller. Consequently, natural increase can decline, even though the death rate itself is also falling.

For example, if birth and death rates change from 30 and 10 to 18 and 8, natural increase changes from 20 to 10 per thousand. This illustrates why option B, “it may decline,” is the most suitable answer. It need not always rise sharply, double, or depend only on migration. The exact result requires actual rates, so “may” is appropriately cautious.

Immigration means people entering a country from other countries. In the population balance, increased immigration adds more people to the receiving country. If births, deaths, and emigration do not change, the extra arrivals make net migration more positive.

As a result, total population is pushed upward, so option D is correct. This wording does not necessarily mean that population must increase by a known amount, because the other components could still offset some of the arrivals. It only identifies the general direction of the effect. Immigration does not automatically raise the death rate or stop migration.

Emigration means residents leave the country to live elsewhere. Population change can be expressed as births minus deaths plus net migration. If births, deaths, and immigration stay unchanged but emigration increases, more people are being lost through migration. Net migration therefore becomes less positive or more negative, reducing the overall population growth rate.

Option A is correct because the immediate effect is to reduce population growth; depending on the size of the increase, the population could even decline. Natural increase is calculated from births and deaths, so it does not rise merely because emigration increases. Emigration does not make the death rate zero, and population growth does not automatically double. These choices confuse separate demographic components.

Population growth is not controlled by one factor alone. Births add people to a population, deaths remove people, and migration moves people into or out of a place. A complete understanding therefore requires all three processes. The correct choice is C, “Births, deaths and migration.”

The change in total population can be represented as natural increase plus net migration: births minus deaths, followed by the balance between in-migration and out-migration. A place may have many births but still lose population if many people move away. Similarly, low natural growth can be offset by large in-migration. Area, density, or urban population may help describe population, but none of them alone explains population change as fully as the three demographic components.

The annual population growth rate compares the increase with the population at the beginning of the period. The formula is \(\text{Growth rate} = \frac{\text{Population increase}}{\text{Initial population}} \times 100\). Substituting the values gives \(25000 \div 1000000 \times 100 = 2.5\) percent.

Thus, the population increased by one-fortieth of its initial size during the year, which is 2.5 percent. Option B is correct. The value 25 percent would result from treating 25,000 as a much larger fraction than it really is. Options A and C do not follow from the stated increase and initial population.

Total population change combines natural increase with net migration. Natural increase is the excess of births over deaths, while net migration is calculated by subtracting people leaving from people entering. A negative net migration means that more people left the country than entered it. The relevant calculation is \(\text{Total change} = \text{Natural increase} + \text{Net migration}\). Substituting the values gives \(100000 + (-150000) = -50000\).

The negative sign means that the country experienced a net decrease of 50,000 people. The natural increase of 100,000 partly offsets the migration loss of 150,000, leaving a difference of 50,000 lost. Therefore, option C is correct. Option A would result if the signs were ignored, while B treats the migration loss as a gain. Option D incorrectly adds the absolute values instead of respecting the negative sign.