Population Growth

A percentage rate is applied to the population base. At the same rate of 1 percent, a larger population produces a larger absolute increase because one percent of a larger number is greater. If the smaller country has population \(P\), its one-year increase is \(0.01P\). The other country has five times that population, \(5P\), so its increase is \(0.01\times5P=0.05P\), which is five times larger. Therefore, the larger country adds more people, and option C is correct.

The percentage rates are equal, but the absolute numbers are not. For example, 1 percent of one million is 10000, while 1 percent of five million is 50000. Birth-rate details are not needed because the question already gives the equal growth rate. The result concerns absolute additions, not which country grows faster proportionally.

The correct answer is C: 900,000 people, or 9 lakh. Absolute increase = initial population × growth rate. Convert 1.5 percent to the decimal 0.015, then calculate 60,000,000 × 0.015 = 900,000. Option A, 300,000, corresponds to only 0.5 percent of 60 million. Option B, 600,000, corresponds to 1 percent. Option C correctly applies 1.5 percent to the whole population. Option D, 1,500,000, would correspond to a 2.5 percent rate, not 1.5 percent. The percentage is a proportion, so it must be converted to a decimal before multiplication. Memory cue: to find people from a percentage, multiply the population by percentage ÷ 100.

A negative growth rate means the population decreases rather than increases. To find the yearly loss, convert the percentage to a decimal and multiply it by the starting population. A rate of 0.5 percent is \(0.005\), because percent means per hundred. The minus sign indicates direction, while the multiplication gives the size of the change.

For a population of 2,000,000, the loss is \(2000000\times0.005=10000\) people. Thus the region loses approximately 10,000 people in one year, so option B is correct. The resulting population would be about 1,990,000, or 19.9 lakh, assuming the rate applies once and remains otherwise unchanged. It is a decrease, not an addition.

Population growth depends mainly on the balance between births and deaths, and migration may also matter. If health improvements reduce deaths before birth rates fall, the gap between births and deaths becomes larger. This produces faster natural increase for a period. Later, when birth rates also decline, the gap becomes smaller and growth slows.

Thus the likely sequence is an initial phase of rapid population growth followed by gradually slower growth. This is consistent with the demographic transition pattern described in the question. Option A is correct. Zero or negative growth is not the immediate result of a falling death rate when births are still relatively high.

The growth rate has changed from 3 percent to 1 percent, so the speed of increase has become lower. However, 1 percent is still a positive rate. This means that the population continues to grow, although fewer people are added proportionally than before. Therefore, choice B is correct. A population would be declining only if the relevant net growth rate became negative.

Suppose the population base were 100 million. At 3 percent, about 3 million people would be added; at 1 percent, about 1 million would be added. The second increase is smaller, but it is still an increase. The statement gives no information proving that density fell, because density also depends on area. It also does not mean growth has ended or that the population is declining.

Population change comes from natural increase plus net migration. Natural increase is births minus deaths. Net out-migration means more people leave than enter, so it is represented as a negative migration value. Both effects must be combined with their signs rather than treated as positive quantities.

Natural increase is \(1000000-700000=300000\). Including net out-migration gives \(300000-400000=-100000\). Therefore, the population decreases by 100000, or 1 lakh, and option A is correct. The 3-lakh natural increase alone would be correct only if migration were ignored.

The correct answer is B: approximately 35 years. The Rule of 70 estimates doubling time as 70 divided by the annual growth rate in percent. Here the rate is 2 percent and there is no migration, so total growth is also 2 percent. Doubling time ≈ 70 ÷ 2 = 35 years. Option A would require a growth rate of about 2.8 percent. Option B follows the Rule of 70 correctly. Option C would match a rate near 1.4 percent. Option D would match about 0.5 percent and is much too long. This is an approximation and assumes the rate remains reasonably constant. Memory cue: for a percentage rate, divide 70 by the number before the percent sign.

The Rule of 70 gives a quick estimate of the time needed for a growing population to double. Its formula is doubling time approximately equal to 70 divided by the annual growth rate expressed as a percentage. The rate must be used as 0.5, not as the decimal 0.005, because the rule already expects a percentage number.

Substitute the given rate: doubling time ≈ 70 ÷ 0.5 = 140 years. Therefore, option D is correct. The result also makes sense conceptually: a growth rate of only half a percent is slow, so doubling takes a long time. A result of 70 years would correspond to a growth rate near 1 percent, while 35 years would correspond to about 2 percent. The Rule of 70 is an approximation and assumes a roughly constant rate.

Natural increase is the birth rate minus the death rate. The given rates are per thousand, but the answer choices are percentages, so the result must be converted. Since one thousand equals one hundred percent in the rate conversion context, a rate per thousand is divided by 10 to express it as a percent.

The natural increase is \(16-11=5\) per thousand. Converting it gives \(5\div10=0.5\) percent. Thus the country gains five persons per thousand through natural change, equivalent to half a percent of the population. The answer is not 5 percent, because that would confuse “per thousand” with “percent.” Option A is correct.

Total population change has two parts: natural change and net migration. Natural change is births minus deaths. If deaths slightly exceed births, natural change is negative. However, immigration adds people, and if immigration minus emigration is larger than the natural loss, the total population can still rise.

For example, a natural decrease of 1,000 combined with net immigration of 5,000 gives a total increase of 4,000. The exact outcome depends on the sizes of the two effects, so the population may increase, remain stable, or decrease. Among the choices, option A is the valid possibility. Option C is wrong because the natural increase remains negative.

Total population change is not determined by the birth rate alone. Natural increase equals births minus deaths, while migration changes population through immigration and emigration. Large-scale emigration can remove many people from the country and may offset, reduce, or even exceed natural increase, depending on the death rate and the size of net migration.

Therefore, the correct conclusion is that total growth depends on births, deaths, and net migration together. A high birth rate does not guarantee rapid total growth. Option B is correct. The statements that growth will always be rapid or always zero ignore the effects of deaths and migration.

The correct answer is B: 10 percent over the full five-year period. First find the absolute increase: 3.3 million − 3 million = 0.3 million. Then compare this increase with the initial population: (0.3 ÷ 3) × 100 = 10 percent. Option A, 5 percent, is half of the correct percentage. Option B uses the correct initial population as the base and gives the total five-year growth. Option C incorrectly divides the final population by the initial population and reports 110 percent rather than the increase. Option D treats the number 3 million as if it were a percentage. This is cumulative growth over five years, not an annual growth rate. Memory cue: percentage increase = (final − initial) ÷ initial × 100.

Percentage decrease measures the fall relative to the original population, not relative to the final population. The original population is 5 million and the final population is 4.75 million. First find the numerical decrease: 5 − 4.75 = 0.25 million, which is 250,000 people. This decrease must then be compared with the original 5 million.

Percentage decrease = (0.25 ÷ 5) × 100 = 5 percent. Therefore, option B is correct. The same calculation in lakhs is (2.5 lakh ÷ 50 lakh) × 100 = 5 percent. The value 2.5 is the absolute decrease in lakh, not the percentage decrease. Using the final population as the denominator would answer a different question and would not give the standard percentage decline.

Absolute growth tells how many people were added, but it does not show the size of the population that produced that increase. Percentage growth divides the increase by the initial population, making the change relative to the starting size. This is especially useful when comparing countries or regions with very different populations.

For example, adding 100,000 people means 10% growth for a population of 1,000,000 but only 1% growth for a population of 10,000,000. Thus percentage growth accounts for the initial population size, so option A is correct. It does not count only births or exclude deaths; the population change may reflect births, deaths and migration.

A stable population means that the overall balance of demographic change is approximately zero. It does not mean that births, deaths, or migration must stop. Natural increase is births minus deaths, and net migration is arrivals minus departures; these components can offset one another.

For example, if births exceed deaths and natural increase is positive, an equal amount of net out-migration can cancel it. The total population can then remain stable even though many demographic events occur. Births and deaths need not be zero, and migration need not stop. Therefore option A is the possible situation and is correct.

Natural increase is found by subtracting the death rate from the birth rate. Total growth then includes net migration. Because the migration rate is negative, it must be added as a negative quantity. Rates are both expressed per thousand, so no unit conversion is needed.

Natural increase is \(14-9=5\) per thousand. Adding net migration gives \(5+(-5)=0\) per thousand. Thus the number of births and in-migration together balances deaths and out-migration, producing no net population change. Option B is correct. A positive 5 per thousand would ignore migration, while a negative 5 per thousand would ignore natural increase.

Total population growth combines natural increase and net migration. Natural increase is calculated as births minus deaths. If deaths exceed births, natural increase is negative. Positive net migration can offset that loss, so it must be added with its sign rather than treated as a separate unrelated figure.

Natural increase is \(9-11=-2\) per thousand. Adding positive net migration gives \(-2+4=+2\) per thousand. Thus the population still grows overall, even though natural change alone would have reduced it. Option B, positive 2 per thousand, is correct. The result is not 4 because migration must be combined with the negative natural increase.

A large young population can create population momentum. Even when each family is choosing fewer children, many young people may soon enter the ages when people commonly have children. The number of potential parents can therefore remain large for some time. As a result, births may continue to exceed deaths and total population growth may not stop immediately. Choice A gives the correct explanation.

Falling fertility changes the average number of children per woman, but it does not instantly remove the large number of people already approaching reproductive ages. This is why population trends respond with a time lag. The statement does not imply that the death rate becomes zero, that migration is always high, or that land area increases. Those options describe unrelated or unsupported conditions, so they cannot explain the continued growth.

A high birth rate does not by itself tell us how rapidly population is increasing. Natural increase depends on the difference between the birth rate and the death rate. If both rates are high and nearly equal, many people may be born, but nearly as many people may die. The resulting difference can therefore be small, producing slow or moderate population growth.

For example, a birth rate of 40 per thousand and a death rate of 38 per thousand give a natural increase of only 2 per thousand. Thus option A is correct. Option B is wrong because birth rate is related to population change. Option C wrongly limits the effect of mortality to migration, and option D makes an unsupported absolute claim. The supplied answer is accurate.

Total population growth can include two components: natural increase and net migration. When both rates are stated for the same year and population, they are added algebraically. The natural increase is 1 percent and the net migration rate is 0.5 percent, so the approximate total growth rate is 1.5 percent. This assumes the rates use the same population base.

One percent of 100 million is 1 million, and 0.5 percent is 500,000. Adding them gives 1.5 million people. Equivalently, 100,000,000 × 0.015 = 1,500,000. Thus, option C, 1.5 million or 15 lakh, is correct. The answer 10 lakh counts only natural increase and ignores migration, while 20 lakh would represent a 2 percent increase rather than the stated 1.5 percent.

A negative growth rate means that the population is decreasing rather than increasing. The stated population is 50 million and the magnitude of the rate is 0.4 percent. To find the number of people lost in one year, convert 0.4 percent to the decimal 0.004 and multiply it by the starting population. The negative sign indicates direction, while the calculated positive number gives the size of the decrease.

Decrease = 50,000,000 × 0.004 = 200,000 people. This is 2 lakh, so option B is correct. After one year, the approximate population would be 49.8 million if the rate remained unchanged. The answer 1 lakh would represent only 0.2 percent of the population, and 4 lakh would represent 0.8 percent, so neither matches the stated rate.

The correct answer is A: 200,000 people, or 2 lakh. The 300,000 gain from births and deaths is the natural increase. Migration causes a loss of 100,000, so its contribution is −100,000. Actual total population growth includes both effects: 300,000 + (−100,000) = 200,000. Option A correctly gives the net result. Option B reports only the natural increase and ignores migration. Option C adds the two magnitudes even though migration is a loss, so it uses the wrong sign. Option D reports only the migration loss and ignores births and deaths. The word “actual” is important because it asks for the final change after all components are combined. Memory cue: gains add, losses subtract; actual growth = natural increase + net migration.

A falling growth rate usually means that births are contributing less to population increase. If this continues, younger age groups may form a smaller share of the population, while people who survive to older ages form a larger share. This gradual change in the age structure is called population ageing and is often associated with slower population growth.

Thus option B, population ageing and slow growth, best matches both clues. A young population with high fertility would normally produce faster growth, not the stated pattern. Rapid population explosion is also inconsistent with declining growth. High immigration alone cannot be concluded because the question gives no evidence about migration and focuses on the age structure.

Absolute growth is the direct numerical difference between final and initial population. Since the question already gives an increase of 500,000, absolute growth is known. Its positive sign also shows that the population increased, so the direction of change is known as well. However, percentage growth is a relative measure.

To calculate percentage growth, we need \(\frac{\text{absolute growth}}{\text{initial population}}\times100\). The initial population is not supplied, so the denominator is unknown and the percentage cannot be calculated directly. Therefore, option C is correct. Different initial populations could produce very different percentages from the same increase of 500,000, which is why the missing starting value matters.

Population growth is affected by both natural change and migration. Natural increase depends on births minus deaths, while net migration depends on immigration minus emigration. To turn these changes into a meaningful growth analysis, we also need the starting population and an appropriate time period. Looking at only population, area, or one rate leaves out important components.

Option C includes births, deaths, immigration, emigration, and the initial population. These data allow calculation of natural increase, net migration, total change, and growth relative to the starting population. Therefore, option C is correct. Population density and urban-rural proportions describe distribution or composition, but they cannot by themselves provide a complete quantitative account of population growth.