To calculate the growth rate, we can use the formula:
[tex]$ r = (CBR - CDR) / 10 $[/tex]
where CBR is the crude birth rate and CDR is the crude death rate, both per 1,000 people. The growth rate will be a percentage, so we need to divide the result by 10.
To calculate the doubling time, we can use the formula:
[tex]$ T_d = 70 / r $[/tex]
where $T_d$ is the doubling time in years and $r$ is the annual growth rate as a decimal.
Using these formulas, we get:
1. United States
- CBR = 13
- CDR = 8
[tex]$r = (13 - 8) / 10 = 0.5\%$[/tex]
[tex]T_d = 70 / 0.005 = 14,000$[/tex]years
2. Mexico
- CBR = 19
- CDR = 5
[tex]$r = (19 - 5) / 10 = 1.4\%$[/tex]
[tex]$T_d = 70 / 0.014 = 5,000$[/tex]
years
3. Japan
- CBR = 8
- CDR = 9
[tex]$r = (8 - 9) / 10 = -0.1\%$[/tex]
[tex]$T_d = 70 / -0.001 = -70,000$[/tex]
years (this negative result means the population is shrinking)
4. United Kingdom
- CBR = 13
- CDR = 9
[tex]$r = (13 - 9) / 10 = 0.4\%$[/tex]
[tex]$T_d = 70 / 0.004 = 17,500$[/tex]
years
5. China
- CBR = 12
- CDR = 7
[tex]$r = (12 - 7) / 10 = 0.5\%$[/tex]
[tex]$T_d = 70 / 0.005 = 14,000$[/tex]
years
6. India
- CBR = 23
- CDR = 7
[tex]$r = (23 - 7) / 10 = 1.6\%$[/tex]
[tex]$T_d = 70 / 0.016 = 4,375$[/tex] years
7. Nigeria
- CBR = 41
- CDR = 16
[tex]$r = (41 - 16) / 10 = 2.5\%$[/tex]
[tex]$T_d = 70 / 0.025 = 2,800$[/tex]
years
8. South Africa
- CBR = 21
- CDR = 14
[tex]$r = (21 - 14) / 10 = 0.7\%$[/tex]
[tex]$T_d = 70 / 0.007 = 10,000$[/tex] years
9. Canada
- CBR = 11
- CDR = 7
[tex]$r = (11 - 7) / 10 = 0.4\%$[/tex]
[tex]$T_d = 70 / 0.004 = 17,500$[/tex]
years
10. Italy
- CBR = 9
- CDR = 10
[tex]$r = (9 - 10) / 10 = -0.1\%$[/tex]
[tex]$T_d = 70 / -0.001 = -70,000$[/tex]
years (again, negative result means population is shrinking)
Answers & Comments
Explanation:
To calculate the growth rate, we can use the formula:
[tex]$ r = (CBR - CDR) / 10 $[/tex]
where CBR is the crude birth rate and CDR is the crude death rate, both per 1,000 people. The growth rate will be a percentage, so we need to divide the result by 10.
To calculate the doubling time, we can use the formula:
[tex]$ T_d = 70 / r $[/tex]
where $T_d$ is the doubling time in years and $r$ is the annual growth rate as a decimal.
Using these formulas, we get:
1. United States
- CBR = 13
- CDR = 8
[tex]$r = (13 - 8) / 10 = 0.5\%$[/tex]
[tex]T_d = 70 / 0.005 = 14,000$[/tex]years
2. Mexico
- CBR = 19
- CDR = 5
[tex]$r = (19 - 5) / 10 = 1.4\%$[/tex]
[tex]$T_d = 70 / 0.014 = 5,000$[/tex]
years
3. Japan
- CBR = 8
- CDR = 9
[tex]$r = (8 - 9) / 10 = -0.1\%$[/tex]
[tex]$T_d = 70 / -0.001 = -70,000$[/tex]
years (this negative result means the population is shrinking)
4. United Kingdom
- CBR = 13
- CDR = 9
[tex]$r = (13 - 9) / 10 = 0.4\%$[/tex]
[tex]$T_d = 70 / 0.004 = 17,500$[/tex]
years
5. China
- CBR = 12
- CDR = 7
[tex]$r = (12 - 7) / 10 = 0.5\%$[/tex]
[tex]$T_d = 70 / 0.005 = 14,000$[/tex]
years
6. India
- CBR = 23
- CDR = 7
[tex]$r = (23 - 7) / 10 = 1.6\%$[/tex]
[tex]$T_d = 70 / 0.016 = 4,375$[/tex] years
7. Nigeria
- CBR = 41
- CDR = 16
[tex]$r = (41 - 16) / 10 = 2.5\%$[/tex]
[tex]$T_d = 70 / 0.025 = 2,800$[/tex]
years
8. South Africa
- CBR = 21
- CDR = 14
[tex]$r = (21 - 14) / 10 = 0.7\%$[/tex]
[tex]$T_d = 70 / 0.007 = 10,000$[/tex] years
9. Canada
- CBR = 11
- CDR = 7
[tex]$r = (11 - 7) / 10 = 0.4\%$[/tex]
[tex]$T_d = 70 / 0.004 = 17,500$[/tex]
years
10. Italy
- CBR = 9
- CDR = 10
[tex]$r = (9 - 10) / 10 = -0.1\%$[/tex]
[tex]$T_d = 70 / -0.001 = -70,000$[/tex]
years (again, negative result means population is shrinking)