SOLUTION: A chemist needs 120millileters of a 21% solution but has only 11% and 71% solutions avaible. Find how many millileters of each that should be mixed to get the desired solution.

Question 715922: A chemist needs 120millileters of a 21% solution but has only 11% and 71% solutions avaible. Find how many millileters of each that should be mixed to get the desired solution.
Answer by josgarithmetic(39617) (Show Source): You can put this solution on YOUR website!
(target matter)/(amount of solution)=(target concentration)

x = volume of 11%
y = volume of 71%

and

Rational equation gives us
11x+71y=120*21

Solve the system for x and y:

Multiplying the simple "120" equation by 11, then we have and . Subtract the second equation from the first and ... find a value for y. Then use the simpler x+y=120 equation to find the value for x.

, 6y=120
, ml. of the 71% solution...
RELATED QUESTIONS
A chemist needs 120 milliliters of a 71% solution but has only 55% and 79% solutions... (answered by josmiceli)

A Chemist needs 120 milliliters of a 21% solution but only has 3% and 27% solutions... (answered by Alan3354)

a chemist needs 90 milliliters of a 26% solution but has only 21% and 30% solutions... (answered by Alan3354)

A chemist needs 140 milliliters of a 33% solution but has only 11% AND 395 solutions... (answered by Alan3354)

A chemist needs 90 milliliters of a 20% solution but only has only 4% and 40% solutions... (answered by richwmiller)

a chemist needs 120 milliliters of a 30% solution but only has only 14% and 38% solutions (answered by josmiceli)

A chemist has 300 millileters (mL) of solution that is 18% acid. How many millileters of (answered by stanbon)

A chemist needs 150 milliliters of a 65% solution but has only 32% and 77% solutions... (answered by stanbon)