Solution Mixture Calculator

How many units of % Solution 1 must be mixed with units of % Solution 2 to get a mixture that is %

How many units of a 100% solution must be mixed with 18 units of 30% to get 50% mixture?

Step 1:
Let x = Number of units of Solution 1
1x + 18 x 0.3 = 0.5(x + 18)
1x + 5.4 = 0.5x + 9

Subtract 50x from both sides of the equation to isolate x:
100x + 5.4 - 0.5x = 0.5x + 9 - 0.5x

Subtract 5.4 from both sides of the equation:
0.5x + 5.4 - 5.4 = 9 - 5.4
0.5x = 3.6

Divide each side of the equation by 0.5
x
0.5
=
3.6
0.5

x = 7.2