Answer
423.9k+ views
Hint: Here it is enough if we find the percentage value at the end of each year and add it with the population of the previous year.
Complete step-by-step answer:
Step 1:
We are given that at present the population is 25000.
Let us consider the present population to be ${P_1}$
${P_1} = 25000$
Now it is given that there is a population rise of 4% in the first year .
This is nothing other than 4% of ${P_1}$, people have increased.
So ,let's find the value of 4% of ${P_1}$,
$
\Rightarrow \dfrac{4}{{100}}*25000 = 4*250 \\
{\text{ }} = 1000 \\
$
Therefore there is a rise of 1000 people at the end of first year .
So now the population at the end of first year is ${P_1} + 1000$
Let the new population be${P_2}$
Therefore
$
{P_2} = {P_1} + 1000 = 25000 + 1000 = 26000 \\
\therefore {P_2} = 26000 \\
$
Step 2:
Now let's repeat the same process with ${P_2}$
Now it is given that there is a population rise of 5% in the second year .
This is nothing other than 5% of ${P_2}$, people have increased.
So ,let's find the value of 5% of ${P_2}$,
$
\Rightarrow \dfrac{5}{{100}}*26000 = 5*260 \\
{\text{ }} = 1300 \\
$
Therefore there is a rise of 1300 people at the end of second year when compared to the previous year.
So now the population at the end of second year is ${P_2} + 1300$
Let the new population be${P_3}$
Therefore
$
{P_3} = {P_2} + 1300 = 26000 + 1300 = 27300 \\
\therefore {P_3} = 27300 \\
$
Step 3:
Now let's repeat the same process with ${P_3}$
Now it is given that there is a population rise of 8% in the third year .
This is nothing other than 8% of ${P_3}$, people have increased.
So ,let's find the value of 8% of ${P_3}$,
$
\Rightarrow \dfrac{8}{{100}}*27300 = 8*273 \\
{\text{ }} = 2184 \\
$
Therefore there is a rise of 2184 people at the end of third year when compared to the previous year.
So now the population at the end of third year is ${P_3} + 2184$
Let the new population be${P_4}$
Therefore
$
{P_4} = {P_3} + 2184 = 27300 + 2184 = 29484 \\
\therefore {P_4} = 29484 \\
$
Therefore the population after three years is 29,484.
The correct option is A
Note: The percent rate is calculated by dividing the new value by the original value and multiplying by 100%. The percentage value or new value is calculated by multiplying the original value by the percent rate and dividing by 100%.
Complete step-by-step answer:
Step 1:
We are given that at present the population is 25000.
Let us consider the present population to be ${P_1}$
${P_1} = 25000$
Now it is given that there is a population rise of 4% in the first year .
This is nothing other than 4% of ${P_1}$, people have increased.
So ,let's find the value of 4% of ${P_1}$,
$
\Rightarrow \dfrac{4}{{100}}*25000 = 4*250 \\
{\text{ }} = 1000 \\
$
Therefore there is a rise of 1000 people at the end of first year .
So now the population at the end of first year is ${P_1} + 1000$
Let the new population be${P_2}$
Therefore
$
{P_2} = {P_1} + 1000 = 25000 + 1000 = 26000 \\
\therefore {P_2} = 26000 \\
$
Step 2:
Now let's repeat the same process with ${P_2}$
Now it is given that there is a population rise of 5% in the second year .
This is nothing other than 5% of ${P_2}$, people have increased.
So ,let's find the value of 5% of ${P_2}$,
$
\Rightarrow \dfrac{5}{{100}}*26000 = 5*260 \\
{\text{ }} = 1300 \\
$
Therefore there is a rise of 1300 people at the end of second year when compared to the previous year.
So now the population at the end of second year is ${P_2} + 1300$
Let the new population be${P_3}$
Therefore
$
{P_3} = {P_2} + 1300 = 26000 + 1300 = 27300 \\
\therefore {P_3} = 27300 \\
$
Step 3:
Now let's repeat the same process with ${P_3}$
Now it is given that there is a population rise of 8% in the third year .
This is nothing other than 8% of ${P_3}$, people have increased.
So ,let's find the value of 8% of ${P_3}$,
$
\Rightarrow \dfrac{8}{{100}}*27300 = 8*273 \\
{\text{ }} = 2184 \\
$
Therefore there is a rise of 2184 people at the end of third year when compared to the previous year.
So now the population at the end of third year is ${P_3} + 2184$
Let the new population be${P_4}$
Therefore
$
{P_4} = {P_3} + 2184 = 27300 + 2184 = 29484 \\
\therefore {P_4} = 29484 \\
$
Therefore the population after three years is 29,484.
The correct option is A
Note: The percent rate is calculated by dividing the new value by the original value and multiplying by 100%. The percentage value or new value is calculated by multiplying the original value by the percent rate and dividing by 100%.
Recently Updated Pages
How many sigma and pi bonds are present in HCequiv class 11 chemistry CBSE
![arrow-right](/cdn/images/seo-templates/arrow-right.png)
Why Are Noble Gases NonReactive class 11 chemistry CBSE
![arrow-right](/cdn/images/seo-templates/arrow-right.png)
Let X and Y be the sets of all positive divisors of class 11 maths CBSE
![arrow-right](/cdn/images/seo-templates/arrow-right.png)
Let x and y be 2 real numbers which satisfy the equations class 11 maths CBSE
![arrow-right](/cdn/images/seo-templates/arrow-right.png)
Let x 4log 2sqrt 9k 1 + 7 and y dfrac132log 2sqrt5 class 11 maths CBSE
![arrow-right](/cdn/images/seo-templates/arrow-right.png)
Let x22ax+b20 and x22bx+a20 be two equations Then the class 11 maths CBSE
![arrow-right](/cdn/images/seo-templates/arrow-right.png)
Trending doubts
Fill the blanks with the suitable prepositions 1 The class 9 english CBSE
![arrow-right](/cdn/images/seo-templates/arrow-right.png)
At which age domestication of animals started A Neolithic class 11 social science CBSE
![arrow-right](/cdn/images/seo-templates/arrow-right.png)
Which are the Top 10 Largest Countries of the World?
![arrow-right](/cdn/images/seo-templates/arrow-right.png)
Give 10 examples for herbs , shrubs , climbers , creepers
![arrow-right](/cdn/images/seo-templates/arrow-right.png)
Difference between Prokaryotic cell and Eukaryotic class 11 biology CBSE
![arrow-right](/cdn/images/seo-templates/arrow-right.png)
Difference Between Plant Cell and Animal Cell
![arrow-right](/cdn/images/seo-templates/arrow-right.png)
Write a letter to the principal requesting him to grant class 10 english CBSE
![arrow-right](/cdn/images/seo-templates/arrow-right.png)
Change the following sentences into negative and interrogative class 10 english CBSE
![arrow-right](/cdn/images/seo-templates/arrow-right.png)
Fill in the blanks A 1 lakh ten thousand B 1 million class 9 maths CBSE
![arrow-right](/cdn/images/seo-templates/arrow-right.png)