Advertisements
Advertisements
Question
The annual rate of growth in population of a certain city is 8%. If its present population is 196830, what it was 3 years ago?
Solution
Population after three years = P \[\left( 1 + \frac{R}{100} \right)^n \]
\[196, 830 = P \left( 1 + \frac{8}{100} \right)^3 \]
\[196, 830 = P \left( 1 . 08 \right)^3 \]
\[P = \frac{196, 830}{1 . 259712}\]
\[ = 156, 250\]
Thus, the population three years ago was 156, 250.
APPEARS IN
RELATED QUESTIONS
A scooter was bought at Rs 42,000. Its value depreciated at the rate of 8% per annum. Find its value after one year.
Compute the amount and the compound interest in the following by using the formulae when:
Principal = Rs 12800, Rate = \[7\frac{1}{2} %\], Time = 3 years
Compute the amount and the compound interest in the following by using the formulae when:
Principal = Rs 10000, Rate 20% per annum compounded half-yearly, Time = 2 years
The difference between the compound interest and simple interest on a certain sum at 15% per annum for 3 years is Rs 283.50. Find the sum.
Three years ago, the population of a town was 50000. If the annual increase during three successive years be at the rate of 4%, 5% and 3% respectively, find the present population.
In a factory the production of scooters rose to 46305 from 40000 in 3 years. Find the annual rate of growth of the production of scooters.
The population of a certain city was 72000 on the last day of the year 1998. During next year it increased by 7% but due to an epidemic it decreased by 10% in the following year. What was its population at the end of the year 2000?
The cost of a T.V. set was quoted Rs 17000 at the beginning of 1999. In the beginning of 2000 the price was hiked by 5%. Because of decrease in demand the cost was reduced by 4% in the beginning of 2001. What was the cost of the T.V. set in 2001?
In a forest there are 40,000 trees. Find the expected number of trees after 3 years if the objective is to increase the number at the rate 5% per year.
The population of a city was 20,000 in the year 1997. It increased at the rate of 5% p.a. Find the population at the end of the year 2000.
