<PRE><B>Question 1095527</B>
let x equal the number of liters of 15% weedkiller.


your equation is .15 * x + .10 * 5 = .12 * (x + 5)


simplify to get .15 * x + .10 * 5 = .12 * x + .12 * 5


simplify further to get .15 * x + .5 = .12 * x + .6


subtract .12 * x from both sides and subtract .5 from both sides and simplify to get .03 * x = .1


divide both sides by .03 to get x = .1 / .03 = 3.333333333 rounded to 9 decimal digits.


you would need 3.333333333 liters of 15% solution to be added to 5 liters of 10% solution to get 8.333333333 liters of 12% solution.


.15 * 3.333333333 = .5
.10 * 5 = .5


.5 + .5 = 1


5 + 3.333333333 = 8.333333333


1 divided by 8.333333333 = .12 which is equal to 12%.


solution looks good.


you would need 3 and 1/3 liters of 15% solution to be added to 5 liters of 10% to get 8 and 1/3 liters of 12% solution.


in decimal form rounded to 2 decimal digits, you would need 3.33 liters of 15% solution to be added to 5 liters of 10% solution to get 8.33 liters of 12% solution.


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