How many liters of a 35% salt solution must be mixed with 20 liters of 70% salt solution to obtain a solution that is 45% salt? What is the equation?

.35 x + .70 (20) = .45(x+20)

50=x

Step-by-step explanation:

Let x = liters of 35% salt solution

We have 20 liters of 70%

We have a total of 20+x liters of 45%

.35 x + .70 (20) = .45(x+20)

Distribute

.35x + 14 = .45x +9

Subtract .35x from each side

14 = .10x +9

Subtract 9 from each side

5 = .10x

Divide each side by .1

5/.1 = x

50=x

answer: ouch. thats difficult

step-by-step explanation:

geometry: triangles

solvers

lessons

answers archive

call the larger triangle abc

then the smaller triangle cde is similar to abc (all angles are equal, aaa).  

ab is the side that is 36, and we wish to find de, the side corresponding to ab

area_cde = area_abc - area_cde --> area_abc / area_cde = 2

let x=length of de

ratio of areas = (ratio of sides)^2

+2+=+%2836%2fx%29%5e2+

+2+=+1296%2fx%5e2+

++x%5e2+=+1296%2f2+=+648+

25.45584