Respuesta :
Given:
A scientist has 5% and a 10% acid solution in his lab.
He needs 270 milliliters of a 20% acid solution.
To find the amount of 25% solution and how many milliliters of the 10% solution should the scientist mix to make the 20% solution:
Here,
The dearer percentage is 25%.
The cheaper percentage is 10%.
The mean percentage is 20%.
Using the mixture and allegation method,
The ratio of the litters of cheaper (10% solution) to dearer value (25% solution) is,
[tex]\begin{gathered} (\text{Dearer value-mean): (Mean-Ch}eaper\text{ value)} \\ (25-20)\colon(20-10) \\ 5\colon10 \\ 1\colon2 \end{gathered}[/tex]So, the number of liters to be taken from 10% solution is,
[tex]\frac{1}{3}\times270=90\text{ liters}[/tex]So, the number of liters to be taken from 25% solution is,
[tex]\frac{2}{3}\times270=180\text{ liters}[/tex]Hence, the answer is
