A chemist plans to mix 10 liters of a 40% acid solution with some 70% to obtain a 50% solution
40% = 0.4
70% = 0.7
50% = 0.5
A chemist plans to mix 10 liters of a 40%. So 10 times of 0.4 = 4
Let x be the some amount of solution of 70%
70% of x = 0.7x
chemist obtain a 50% of solution
Amount of mixture is 10 + x
So 10+x of 50% = (10+x)*0.5
Now we frame an equation
10 * 0.4 + x * 0.7 = (10+x) * 0.5
4 + 0.7x = 5 + 0.5x
Subtract 4 and 0.5x on both sides
0.2 x= 1
Divide by 0.2
So x= 5
5 liters of 70% of solution is used.
