Question 1 The birth and death rates of a particular city are given below. Study the chart carefully and answer the given questions:

Calculate the average number of births in the city between 2001 to 2005.

a. 4.4 million

b. 4 million

c. 2.8 million

d. 3.2 billion

From the graph, calculate the values of total births between 2001 to 2005. Then find the average of them.

So, average births = (3.5 + 4 + 5 + 3 + 6.5)/ 5 = 4.4.

Therefore, the average births between 2001 to 2005 is 4.4 million (since units are in millions).

Hence, option (c) is the answer.

By what percent (approx.) did the number of births increased in 2005 from the previous year?

a. 180

b.150

c.90

d.117

Solution:

Increase in deaths from 2004 to 2005  = 6.5 – 3 = 3.5 million

Percentage increase in deaths = (3.5 / 3) × 100 = 116.66 %.

The closest option is 117 %, hence the answer will be option (d).

Calculate the difference between the number of deaths and the number of births over the years.

a.5million

b.6million

c.1billion

d.3million

Solution:

Total deaths over the years = 27 

Total births over the years = 22

The difference in deaths and births = 27 – 22 = 5.

Hence, the correct answer will be option (a) i.e. 5 million.

In which year the percentage increase in birth rate over the previous year was the maximum?

a.2001

b.2002

c.2003

d.2004

e. 2005

Solution: 

Percentage increase or decrease for any given year = (difference of values from previous year/ value in that year) × 100.

For 2002, percentage increase  = (4 – 3.5) × 100 = 50 %.

For 2003, percentage increase = 100 %.

For 2004, percentage increase = 200 % (decrease).

For 2005, percentage increase is = 350 %.

Therefore, percentage increase was highest in 2005 and so, option (e) is the correct answer.