15 liters of mixtures contains 20 percent alcohol and the rest water. If 3 liters of water be mixed with it, the percentage of alcohol in the new mixture would be
$
{\text{a}}{\text{. 15 percent}} \\
{\text{b}}{\text{. 16}}\dfrac{2}{3}{\text{ percent}} \\
{\text{c}}{\text{. 17 percent}} \\
{\text{d}}{\text{. 18}}\dfrac{1}{2}{\text{ percent}}{\text{.}} \\
$
Last updated date: 26th Mar 2023
•
Total views: 309k
•
Views today: 8.85k
Answer
309k+ views
Hint – Assume any variable be the liters of alcohol then first try to find out liters of alcohol as variable is the 20 percent of 15 so, use this concept to reach the solution of the problem.
Given data
15 liters of mixtures contains 20 percent alcohol and the rest water.
Let alcohol be x liters.
So, water will be (15 - x) liters.
Now, according to the given condition, x is the 20 percent of 15.
$ \Rightarrow x = \dfrac{{20}}{{100}} \times 15 = \dfrac{{15}}{5} = 3$ Liters.
So water will be (15 - 3) = 12 liters.
Now it is given that 3 liters of water is mixed with the mixture.
So, total liters in the new mixture will be $\left( {15 + 3} \right) = 18$liters.
Now we have to find out percentage of alcohol in new mixture,
Let, the percentage of alcohol in the new mixture be y.
So, y is equal to liters of alcohol divided by total liters in the new mixture multiplied by 100.
$y = \dfrac{3}{{18}} \times 100 = \dfrac{{100}}{6} = \dfrac{{50}}{3} = 16\dfrac{2}{3}$ Percent.
So, $16\dfrac{2}{3}$ is the required percentage of alcohol in the new mixture.
Hence, option (b) is correct.
Note – In such types of questions first find out the liters of alcohol from the given mixture as above, then calculate the value of total liters in the new mixture, then divide liters of alcohol to the total liters in the new mixture and multiply by 100, which is the required percentage of alcohol in the new mixture.
Given data
15 liters of mixtures contains 20 percent alcohol and the rest water.
Let alcohol be x liters.
So, water will be (15 - x) liters.
Now, according to the given condition, x is the 20 percent of 15.
$ \Rightarrow x = \dfrac{{20}}{{100}} \times 15 = \dfrac{{15}}{5} = 3$ Liters.
So water will be (15 - 3) = 12 liters.
Now it is given that 3 liters of water is mixed with the mixture.
So, total liters in the new mixture will be $\left( {15 + 3} \right) = 18$liters.
Now we have to find out percentage of alcohol in new mixture,
Let, the percentage of alcohol in the new mixture be y.
So, y is equal to liters of alcohol divided by total liters in the new mixture multiplied by 100.
$y = \dfrac{3}{{18}} \times 100 = \dfrac{{100}}{6} = \dfrac{{50}}{3} = 16\dfrac{2}{3}$ Percent.
So, $16\dfrac{2}{3}$ is the required percentage of alcohol in the new mixture.
Hence, option (b) is correct.
Note – In such types of questions first find out the liters of alcohol from the given mixture as above, then calculate the value of total liters in the new mixture, then divide liters of alcohol to the total liters in the new mixture and multiply by 100, which is the required percentage of alcohol in the new mixture.
Recently Updated Pages
If ab and c are unit vectors then left ab2 right+bc2+ca2 class 12 maths JEE_Main

A rod AB of length 4 units moves horizontally when class 11 maths JEE_Main

Evaluate the value of intlimits0pi cos 3xdx A 0 B 1 class 12 maths JEE_Main

Which of the following is correct 1 nleft S cup T right class 10 maths JEE_Main

What is the area of the triangle with vertices Aleft class 11 maths JEE_Main

KCN reacts readily to give a cyanide with A Ethyl alcohol class 12 chemistry JEE_Main

Trending doubts
What was the capital of Kanishka A Mathura B Purushapura class 7 social studies CBSE

Difference Between Plant Cell and Animal Cell

Write an application to the principal requesting five class 10 english CBSE

Ray optics is valid when characteristic dimensions class 12 physics CBSE

Give 10 examples for herbs , shrubs , climbers , creepers

Tropic of Cancer passes through how many states? Name them.

Write the 6 fundamental rights of India and explain in detail

Write a letter to the principal requesting him to grant class 10 english CBSE

Name the Largest and the Smallest Cell in the Human Body ?
