The population of village is 1,00,000. The rate of increase is 10% per annum. Find the population at the start of the third year?
A. 1,33,100
B. 1,21,000
C. 1,18,800
D. 1,20,000
E. None of these
Answer: Option B
Solution (By Examveda Team)
100000 == 10%↑(1st year) ==> 110000 == 10%↑(2nd year) ==> 121000 Population at starting of 3rd year = 121000 [By using net percentage change method, we have saved our self from cumber some formulas on population which is based on compound interest].This Question Belongs to Arithmetic Ability >> Percentage
It can be done with the successive formula.
10+10+10*10/100=21
To find the population at the start of the third year, we need to calculate the population after two years of growth.
Given:
Initial population (at the start of the first year) = 100,000
Rate of increase = 10% per annum
To calculate the population after one year, we can use the formula:
Population after one year = Initial population + (Rate of increase * Initial population)
Population after one year = 100,000 + (0.10 * 100,000) = 100,000 + 10,000 = 110,000
Now, to calculate the population after two years, we can use the same formula:
Population after two years = Population after one year + (Rate of increase * Population after one year)
Population after two years = 110,000 + (0.10 * 110,000) = 110,000 + 11,000 = 121,000
Therefore, the population at the start of the third year is 121,000.
The correct answer is B. 1,21,000.
10% = 1/10. 10..... 11... For 1'st yr
10......11....for 2nd year
*- - - - *- - - -
100. 121
100--->100000. Then
121...... = 121000