Question

Study the bar graph representing the number of persons in various age groups in a town shown in Fig. 23.9. Observe the bar graph and answer the following questions:

(i) What is the percentage of the youngest age-group persons over those in the oldest age group?

(ii) What is the total population of the town?

(iii) What is the number of persons in the age-group 60-65?

(iv) How many persons are more in the age-group 10-15 than in the age group 30-35?

(v) What is the age-group of exactly 1200 persons living in the town?

(vi) What is the total number of persons living in the town in the age-group 50-55?

(vii) What is the total number of persons living in the town in the age-groups 10-15 and 60-65?

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(vii) Whether the population in general increases, decreases or remains constant with the increase in the age-group.

Answer 1

(1) The youngest age-group is 10-15 years. The number of persons belonging to this group is 1400. The oldest age-group is 70-75 years. The number of persons belonging to this group is 300. The percentage of youngest age-group persons over those in the oldest group is

(2) The population of the town is

(3) The number of persons in the age group 60-65 is 800.

(4) The number of persons in the age group 10-15 is 1400 and the number of persons in the age group 30-35 is 1100. Hence the number of more persons in the age group 10-15 than the group 30-35 is 1400 – 1100

(5) The age group of 1200 persons living in the town is 20-25.

(6) The total number of persons living in the town in the age-group 50-55 is 900.

(7) The total number of persons living in the town in the age-groups 10-15 and 60-65 is 1400 + 800

(8) It is shown from the bar graph that the height of the bars decreases as the age-group increases.

Hence, the population decreases with the increases in the age-group.