I guess the chef is making the mixture for the sheriff... Let <em>x</em> be the amount of dressing with 5% vinegar that is required, and <em>y</em> the amount of 15% vinegar dressing (both amounts in mL).
The sheriff wants 390 mL of the mixed dressing, so that
<em>x</em> + <em>y</em> = 390
<em>x</em> mL of the 5% dressing contains 0.05<em>x</em> mL of vinegar, while <em>y</em> mL of the 15% dressing contains 0.15<em>y</em> mL of vinegar. The resulting mixture should have a concentration of 9% vinegar, so that it contains 0.09 (390 mL) = 35.1 mL of vinegar. This means
0.05<em>x</em> + 0.15<em>y</em> = 35.1
Solve for <em>x</em> and <em>y</em> :
<em>y</em> = 390 - <em>x</em>
0.05<em>x</em> + 0.15 (390 - <em>x</em>) = 35.1
0.05<em>x</em> + 58.5 - 0.15<em>x</em> = 35.1
23.4 = 0.10<em>x</em>
<em>x</em> = 234
<em>y</em> = 156
First:
2x + 2z = 4
2(x+z)=4
x+z=4/2
x=2-z
-x - y - z= -8
-(2-z)-y-z= -8 replace x
-2+z-y-z= -8 (cancel z)
-2-y= -8
6 = y
Then:
-4x + 4y + 5z = 7 replace x and y
-4(2-z)+4*6 + 5z = 7
-8 + 4z + 24 + 5z = 7
16 + 9z = 7
9z = 7 - 16
9z = -9
z = -9/9
z= -1
Finally
x= 2-z replace z
x = 2- (-1)
x = 3
The given equation is

To solve for x, we have to subtract 8 to both sides

Now we need to get rid of -9 from the left side, and for that we do division


Step-by-step explanation:
it ia 76.92 is the percentage for 10/13
<h3>
Answer: 1/6</h3>
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Explanation:
Let's say for example this pizza had 6 slices to start with. Two-thirds of this is (2/3)*12 = 4 slices. So you have 4 slices left over from yesterday. Then let's say you hand one slice to each of your four friends. Each friend would have 1/6 of the original pizza.