Question

A mixture of milk contains 7 parts of milk and 3 parts of water. Find the percentage of milk in the mixture.

Answer 1

Hint:Assume 100 liters of the mixture. The quantity of milk is 7 parts. In 100 liters of the mixture, the quantity of the milk will be 70 liters. We have a total of 100 liters of mixtures. Now, solve it further and calculate the percentage of milk in the mixture.

Complete step-by-step answer:
According to the question, it is given that we have 7 parts of milk and 3 parts of water in a mixture.
Let us assume that we have 100 liters of the mixture.
If we have 10 parts of the mixture then 7 parts will be of milk and 3 parts will be of water.
The quantity of milk present in the 100 liters of mixture = \[100\times \dfrac{7}{7+3}=70\] liters.
Percentage of milk in the mixture = \[\dfrac{quantity\,of\,milk\,in\,the\,mixture}{total\,quantity\,of\,the\,mixture}\times 100\]
\[=\dfrac{70\,liters}{100\,liters}\times 100\]
= 70
Therefore, the percentage of milk in the mixture is 70%.

Note: We can solve this question in another way. We can take the given parts that is 7 parts of milk and 3 parts of water present in the mixture in the ratio as 7:3.
Let the ratio be x.
The quantity of milk = 7x.
The quantity of water = 3x.
The quantity of mixture = 7x + 3x = 10x.
Now, Percentage of milk in the mixture = \[\dfrac{quantity\,of\,milk\,in\,the\,mixture}{total\,quantity\,of\,the\,mixture}\times 100\]
\[=\dfrac{7x}{10x}\times 100\]
= 70
Therefore, the percentage of milk in the mixture is 70%.