Problema Solution

A chemist needs 130 milliliters of 69% solution but only 65% and 78% solutions available. Find how many militiers of each that should be mixed to get the desired solution

Answer provided by our tutors

let


x = milliliters of 65% solution

y = milliliters of 78% solution


by mixing x and y we need to obtain 130 milliliters of 69% solution


x + y = 130


65% of x + 78% of y = 69% of 130


0.65*x + 0.78*y = 0.69*130


by solving the system of equation


x + y = 130

0.65*x + 0.78*y = 0.69*130


we find


x = 90 ml


y = 40 ml


we need 90 ml of 65% solution and 40 ml of 78% solution.