The population of a town increases by 10% per annum for two years then decreases by 10% per annum for the next two years, if the population of the town four year ago was 10000, what would it be today?
Pick one.
A) 9500	B) 9801	C) 10100	D) 9000	E) None of these
Explanation :   Increase of population = (100+10)= 
<gadget id="calculator">(100+10)</gadget>
<output>110</output>
110%= 1.1   Reduction of population = (100 -10)= 
<gadget id="calculator">(100 -10)</gadget>
<output>90</output>
90%= 0.9   Total effect = 1.1 X 1.1 X 0.9 X 0.9 = 0.9801,   Population = 10000 X 0.9801 = 9801   Answer : 9801
<result>B</result>
The population of a town increases by 10% per annum for two years then decreases by 10% per annum for the next two years, if the population of the town four year ago was 10000, what would it be today?