Which of the following are in inverse proportion?
(i) The number of workers on a job and the time to complete the job
(ii) The time taken for a journey and the distance travelled in a uniform speed
(iii) Area of cultivated land and the crop harvested
(iv) The time taken for a fixed journey and the speed of the vehicle
(v) The population of a country and the area of land per person

Solution:

If two quantities are related in such a way that an increase in one quantity leads to a corresponding proportional decrease in the other, then such a variation is called inverse proportion.

(i) The number of workers on a job and the time to complete the job.

As the number of workers increases; the job will take less time to complete. Hence, they are inversely proportional.

(ii) The time taken to a journey and the distance travelled in a uniform speed.

In more time, more distance can be travelled. Hence, they are not inversely proportional.

(iii) Area of cultivated land and the crop harvested.

More the area of land cultivated, more crops will be harvested. Hence, they are not inversely proportional.

(iv) The time taken for a fixed journey and the speed of the vehicle.

If speed is increased, it will take less time to complete the fixed journey. Hence, they are inversely proportional.

(v) The population of a country and the area of land per person.

If the population of a country increases, then the area of land per person will be decreased. Hence, they are inversely proportional.

☛ Check: NCERT Solutions for Class 8 Maths Chapter 13

Video Solution:

Which of the following are in inverse proportion?(i) The number of workers on a job and the time to complete the job(ii) The time taken for a journey and the distance travelled in a uniform speed(iii) Area of cultivated land and the crop harvested(iv) The time taken for a fixed journey and the speed of the vehicle(v) The population of a country and the area of land per person

NCERT Solutions Class 8 Maths Chapter 13 Exercise 13.2 Question 1

Summary:

For the following statements, (i) The number of workers on a job and the time to complete the job (ii) The time taken for a journey and the distance travelled in a uniform speed (iii) Area of cultivated land and the crop harvested (iv) The time taken for a fixed journey and the speed of the vehicle (v) The population of a country and the area of land per person the answers are: (i) Inversely proportional (ii) Not inversely proportional (iii) Not inversely proportional (iv) Inversely proportional (v) Inversely proportional

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