Let 
be the number of liters of the 10% solution to be used, and 
the number of liters of the 4% solution. The chemist wants to end up with a 4 liter solution, so
For each liter used in the mixture, a concentration of either 10% or 4% acid will be contributed, and the goal is to make a 4L solution whose concentration is 7%, which means
Solving for 
gives 
, so 2L of both solutions is needed.
Ten times two is equal to twenty.
From the least to greatest from the fractions are: -1/19, -4/7, and 7/4.
And the answer is D.
Answer:
40 quarts
Step-by-step explanation:
1 gallon=4
4•10=40
Answer:
16° and 52°
Step-by-step explanation:
The sum of the angles of a quadrilateral is 360.
360 - 244 - 48 = 68
68 is the sum of the two angles that are in a ratio of 4:13
So, let 4x = measure of one of the angles
and 13x = measure of the other angle
Then 4x + 13x = 68
17x = 68
x = 4
4x = 16 and 13x = 52
Therefore, the measures of the two angles are 16 and 52
Check: 16 + 52 + 244 + 48 = 360 and 16:52 = 4:13
