Population Growth

Correct answer: A. Births, deaths and migration

Direct answer: Option A. Population growth is determined by demographic components: births, deaths and migration. Births increase the number of people, deaths decrease it, and migration changes the population when people enter or leave an area. A useful equation is change = births − deaths + in-migration − out-migration. Option A contains the three broad components correctly. Option B lists soil, climate and slope. These are physical factors that may influence where people live, but they are not direct components of population growth. Option C lists water bodies, which may affect settlement but do not themselves measure demographic change. Option D lists parts of the natural environment and wildlife, not population processes. A common confusion is to mix factors affecting population distribution with components that calculate population change. Memory cue: for growth, remember “births, deaths and movement.”

Correct answer: A. Because fewer people die and more population remains

Direct answer: Option A. Population change is calculated by considering additions and reductions. Births add people, while deaths subtract people. When the death rate declines, fewer people are removed from the population during the period. If births continue, or if births are greater than deaths, the natural increase becomes larger and population growth may rise. Option A expresses this basic idea correctly. Option B is wrong because a fall in deaths does not make births zero; births and deaths are separate demographic events. Option C is wrong because a change in death rate does not reduce the physical area of a place. Option D is wrong because migration can still occur whether the death rate is high or low. The answer says “can” increase because the exact total also depends on births and migration. Memory cue: deaths are a subtraction; reducing the subtraction can increase the result.

Correct answer: B. 20 percent

Correct answer: B, 20 percent. First find the absolute increase: final population minus initial population equals 12 lakh minus 10 lakh, or 2 lakh. Next compare that increase with the initial population, because percentage growth is calculated from the starting value. The formula is: growth percentage = (increase ÷ initial population) × 100. Therefore, (2 ÷ 10) × 100 = 20 percent. A is wrong because 2 lakh is one-fifth, not one-tenth, of 10 lakh. C and D are also too large and do not result from the formula. Memory cue: subtract first, then divide by the original number—not the final number.

Correct answer: B. Decrease of 5 lakh

Correct answer: B, a decrease of 5 lakh. Compare the final value with the initial value: 45 lakh is smaller than 50 lakh, so the direction is a decrease. Subtract the smaller number from the larger number: 50 lakh − 45 lakh = 5 lakh. Thus the population has fallen by 5 lakh. A is incorrect because, although the decrease equals 10% of the initial population, it is not an increase. C reverses the direction of change, and D claims that 50 lakh people were added, which did not happen. If a percentage were asked, the fall would be (5 ÷ 50) × 100 = 10%. Memory cue: check direction first, then calculate the difference.

Correct answer: A. Because growth shows the change in population over time

Direct answer: A is correct. Growth describes change, so it requires comparison between at least two points in time. If a place has 2,000 people in one year and 2,500 in a later year, the difference shows an increase of 500 people during that period. A single year can tell us the population size at that time, but it cannot by itself show whether the number is rising, falling or remaining stable. B is wrong because a population can be counted or estimated for one year; that figure simply does not show growth alone. C is wrong because area is not the sole cause or measure of population growth. D is wrong because weather may influence some conditions, but population growth is studied through population change and its demographic causes. Memory cue: one date gives size; two dates reveal change.

Correct answer: B. Population is more likely to increase

Direct answer: B is correct. Population change can be understood by considering births, deaths and migration. When births are greater than deaths, the area has a natural increase. If out-migration is low, relatively few people are leaving, so this increase is not greatly reduced by movement out of the area. Therefore, the population is more likely to rise, assuming no unusual factor reverses the result. A is wrong because a decrease would normally require deaths to exceed births or substantial out-migration. C is wrong because the stated conditions do not make the population zero. D is wrong because population means the number of people, whereas area means the extent of land. The phrase “more likely” is appropriate because population change can include other factors. Memory cue: more births than deaths adds people; fewer departures allow the increase to remain.

Correct answer: A. 500

Direct answer: A, 500. Absolute growth is the numerical difference between the later population and the earlier population. Write the values in order: later population = 2,500 and earlier population = 2,000. Subtract: 2,500 − 2,000 = 500. Thus, the population increased by 500 people. B is the earlier population, not the amount of increase. C is the later or final population, not the difference between the two years. D results from adding the two populations, 2,000 + 2,500, but addition is not the method for finding absolute growth. No rate or percentage is requested, so there is no need to divide by the base population or multiply by 100. Memory cue: absolute growth = final population − initial population.

Correct answer: C. Ten years

The direct answer is C: ten years. The word decadal comes from a term meaning ten, so a decadal measure covers a period of ten years. To study decadal population growth, compare the population at the beginning of a decade with the population at its end, and then calculate the change or growth rate. Option A is wrong because one year is an annual period. Option B is wrong because five years is a five-year period, not a decade. Option C is correct because one decade equals ten years. Option D is wrong because twenty years covers two decades. Memory cue: annual means one year, decadal means ten years, and a twenty-year period contains two decades.

Correct answer: A. Numerical difference between population of two times

Direct answer: A is correct. Absolute growth is the actual numerical change in population between two points of time. To find it, subtract the earlier population from the later population: absolute growth = later population − earlier population. If a place has 20,000 people at the first census and 23,000 at the next, its absolute growth is 3,000 people. This measure may be positive when population increases, negative when it decreases, or zero when there is no change. A is therefore the exact definition. B is wrong because population divided by area gives population density, not absolute growth. C is wrong because birth rate counts births in relation to population or time and does not include the full population change. D is wrong because death rate measures deaths and also does not represent the difference between two population totals. Memory cue: absolute growth is a subtraction of two population totals; density is population divided by area.

Correct answer: A. Population growth

The correct answer is A: the increase is population growth. Population growth means a change in the number of people over a period, and a rise between two censuses is direct evidence of such an increase. A census provides population information at a particular time, so comparing two census counts shows how the population has changed. B is wrong because density means population per unit of area and requires an area comparison. C is wrong because distribution describes how people are spread across places, not simply whether the total number rose. D is wrong because sex ratio compares the numbers of males and females. Memory cue: change across time is growth; people per area is density; spread across space is distribution.

Correct answer: D. Soil colour

The correct answer is D: soil colour is not a direct component of population growth. Population change is directly related to births, deaths and migration. Births add people, deaths remove people, and migration includes movement into or out of the area. These components can be used to understand why the population total changes. A is wrong because births directly increase population. B is wrong because deaths directly reduce population. C is wrong because in-migration adds people and out-migration removes them. D is correct because soil colour by itself is not part of the demographic calculation, although physical conditions may sometimes influence settlement indirectly. Memory cue: calculate population change with births, deaths and migration, not unrelated descriptive features.

Correct answer: A. Difference between births and deaths

The correct answer is A: natural increase is the difference between births and deaths. It is calculated as births minus deaths during a particular period. If births are greater than deaths, natural increase is positive; if deaths are greater, it is negative; if they are equal, it is zero. Migration is not included in natural increase, although it affects total population change. A is correct because it gives the proper demographic definition. B is wrong because immigration and emigration describe migration, not natural increase, and their net effect is considered as in-migration minus out-migration. C is wrong because area and density describe spatial relationships. D is wrong because rainfall and temperature are environmental elements, not the formula for natural increase. Memory cue: “natural” means births and deaths; movement belongs to migration.

Correct answer: C. Growth of ten years

Answer: C, decadal growth means the increase in population over a period of ten years. The word “decadal” comes from “decade,” which means ten years. To find the absolute decadal growth, subtract the population at the beginning of the decade from the population at its end. If the starting population was 40 lakh and the ending population was 50 lakh, the absolute decadal growth was 10 lakh. A is wrong because one year is annual growth. B is wrong because five years is a five-year or quinquennial period, not a decade. D is wrong because fifty years covers five decades. Decadal growth may be reported as an absolute number or as a percentage, but the time interval remains ten years. Memory cue: decade and decadal both point to ten.

Correct answer: A. Two lakh

Answer: A, the absolute growth is two lakh. Absolute growth is the actual numerical increase in population, so use the formula: current population − earlier population. Here, 12 lakh − 10 lakh = 2 lakh. This calculation does not express a percentage; it gives the number of additional people. A is correct because it is the difference between the two population figures. B is wrong because 10 lakh is the earlier population, not the increase. C is wrong because 12 lakh is the current population, not the amount added. D is wrong because adding the two populations, 10 lakh + 12 lakh, does not measure growth. If the current population were smaller than the earlier population, the result would be a negative change, showing a decline. Memory cue: absolute growth means “how many more,” so subtract the old value from the new value.

Correct answer: B. Twenty percent

Answer: B, the approximate growth percentage is 20%. First find the increase: 60 lakh − 50 lakh = 10 lakh. Then compare this increase with the earlier population, not the current population. Growth percentage = (increase ÷ earlier population) × 100 = (10 ÷ 50) × 100 = 20%. A is wrong because 10 lakh is the absolute increase, not the percentage. C is wrong because 50 lakh is the earlier population, not the calculated rate. D is wrong because 60 lakh is the current population and is not itself a percentage. The denominator matters: percentage growth is measured from the starting population. Memory cue: subtract first, then divide by the old population, and finally multiply by 100.

Correct answer: B. Immigration

Correct answer: B, immigration. Population growth is affected by births, deaths, and migration. When a city offers more jobs, people living in villages or other towns may move into that city to work. This movement into a place is called immigration or inward migration. A is incorrect because emigration means people moving out of the city, which can reduce its population. C is incorrect because death rate measures deaths and is not the direct result of attractive job opportunities. D is incorrect because area is the size of land, not a population-growth component. The same job opportunity can attract migrants even if the city’s land area does not change. Memory cue: “in” in immigration means people come in; “e” in emigration can remind you of exiting.

Correct answer: A. Local growth may decrease

Correct answer: A, local growth may decrease. When young people leave a village to work elsewhere, the movement is called out-migration or emigration from the village. The village loses part of its population, and it may also have fewer people in the age groups that commonly form families. Therefore, local population growth can slow down or even become negative, although the exact result depends on births, deaths, and people returning. B is wrong because leaving cannot necessarily make local growth rapid. C is wrong because birth rate does not always rise; it may fall when many young adults leave. D is wrong because a census can still be conducted whether people migrate or not. Memory cue: out-migration means “out”; people leave, so the place they leave may lose population.

Correct answer: A. Demand and pressure may increase

Correct answer: A. Population growth means that more people may need food, water, land, energy, housing, transport, education, and health services. If the supply of these resources and services does not increase at the same pace, demand and pressure on them can rise. A is carefully worded as “may” because the actual result depends on resource availability, technology, management, and planning. B is wrong because resources do not automatically become unlimited when population increases. C is wrong because every person still needs water, and total water demand may rise. D is wrong because more people generally create greater, not smaller, housing needs. High growth does not always guarantee shortage, but it creates a stronger need for careful planning. Memory cue: more people usually mean more needs.

Correct answer: A. Growth rate

Direct answer: Option A, growth rate, is correct. The pace of growth means how quickly a population changes during a stated period. Growth rate expresses this change in relation to the population, commonly as a percentage. A simple form is: growth rate = population increase divided by the initial population, multiplied by 100. This allows us to compare areas or periods of different size. Option B describes the physical character of soil and does not measure population change. Option C describes a river, not the speed of demographic change. Option D counts wildlife, not human population growth. These factors may matter in environmental or geographical studies, but they are not the requested population indicator. Memory cue: when the question asks “how fast,” look for a rate rather than a size, feature or count.

Correct answer: B. Four lakh

Direct answer: Option B, four lakh, is correct. Absolute growth means the actual numerical increase between two population counts. Use the current population minus the earlier population: 24 lakh − 20 lakh = 4 lakh. No percentage calculation is needed because the question asks for an absolute number. Option A, two lakh, results from an incorrect subtraction. Option B is the difference and therefore the correct answer. Option C is only the earlier population, not the increase. Option D is the current population, not the amount by which it increased. The word “absolute” is important: it asks for the number added, whereas percentage growth would compare that increase with the earlier population. Memory cue: for absolute growth, always perform current minus previous.

Correct answer: B. Twenty percent

Direct answer: Option B, twenty percent, is correct. Percentage growth compares the increase with the population at the beginning of the period. Here, the increase is 8 lakh and the previous population is 40 lakh. First divide: 8 ÷ 40 = 0.2. Then multiply by 100: 0.2 × 100 = 20%. Equivalently, growth percentage = (increase ÷ previous population) × 100. Option A, 10%, is only half the calculated value. Option B matches the formula. Option C, 40%, incorrectly uses the previous population as though it were the percentage increase. Option D, 8%, treats the numerical increase in lakh as a percentage without comparison. Memory cue: the earlier population is the denominator in growth percentage.

Correct answer: B. Twenty percent

Direct answer: B, twenty percent. Growth percentage tells us how much the population increased compared with the starting, or previous, population. First calculate the actual increase: 18 lakh − 15 lakh = 3 lakh. Now use the formula: growth percentage = (increase ÷ previous population) × 100. Therefore, (3 ÷ 15) × 100 = 0.2 × 100 = 20%. A is incorrect because 10% of 15 lakh is only 1.5 lakh. C is incorrect because 30% of 15 lakh is 4.5 lakh, not 3 lakh. D is incorrect because 50% of 15 lakh is 7.5 lakh. The denominator must be the previous population, not the current population or just the numerical increase. Memory cue: percentage growth = increase divided by original value, multiplied by 100.

Correct answer: B. 25 percent

Answer: B, 25 percent. Percentage growth is calculated using the initial population as the base, not the final population. First find the absolute increase: 50 lakh − 40 lakh = 10 lakh. Next divide this increase by the initial population: 10 ÷ 40 = 0.25. Finally multiply by 100: 0.25 × 100 = 25%. Therefore, the population has grown by 25 percent. A is incorrect because 20% would result from using an unsuitable comparison rather than the correct initial base. B is correct because it follows the standard formula: percentage growth = (increase ÷ initial population) × 100. C is incorrect because 40 lakh is the starting amount, not the percentage increase. D is incorrect because 50 lakh is the final population, not the percentage growth. A useful memory cue is: subtract first, then divide by the starting value, and multiply by 100.

Correct answer: A. Population change over a period of ten years

Answer: A. The word “decadal” comes from “decade,” which means a period of ten years. Therefore, decadal population growth refers to the change in population measured over ten years. To study it, compare the population at the beginning of the decade with the population at its end; the result may be expressed as an absolute change or, when required, as a percentage. A is correct because it connects the term with both population and a ten-year period. B is wrong because rivers are unrelated to the population-growth measure. C is wrong because mountain height is a physical geography measurement, not a population change. D is wrong because crop colour has no connection with the definition. The term does not mean ten separate objects; it describes a time interval. Memory cue: decade = ten years, so decadal growth = population change in ten years.

Correct answer: A. 15 lakh and 20 percent

Correct answer: A, 15 lakh and 20 percent. First find the absolute increase: final population minus initial population = 90 lakh − 75 lakh = 15 lakh. Next calculate percentage growth using the initial population as the base: (increase ÷ initial population) × 100 = (15 ÷ 75) × 100 = 20%. A is correct because both parts use the proper steps. B is wrong because 15 is not 25% of 75; it is one-fifth, or 20%. C is wrong because 90 lakh is the final population, not the increase. D is wrong because populations are not added to find growth, and its percentage is also incorrect. A useful rule is: absolute growth = final − initial; percentage growth = absolute growth ÷ initial × 100.