Answer:
-1
Step-by-step explanation:
The mean is the sum of all values divided by the amount of values.
We take the sum of all the numbers:
-3 + -8 + 12 + -15 + 9
-11 + 12 + -15 + 9
1 + -15 + 9
10 + -15
-5
We then divide the sum by how many number we have (we are given 5 numbers):
-5/5 = -1
Therefore, our mean is equal to -1.
116 if you add 72 plus 43
<span> 7x+2y=5;13x+14y=-1 </span>Solution :<span><span> {x,y} = {1,-1}</span>
</span>System of Linear Equations entered :<span><span> [1] 7x + 2y = 5
</span><span> [2] 13x + 14y = -1
</span></span>Graphic Representation of the Equations :<span> 2y + 7x = 5 14y + 13x = -1
</span>Solve by Substitution :
// Solve equation [2] for the variable y
<span> [2] 14y = -13x - 1
[2] y = -13x/14 - 1/14</span>
// Plug this in for variable y in equation [1]
<span><span> [1] 7x + 2•(-13x/14-1/14) = 5
</span><span> [1] 36x/7 = 36/7
</span><span> [1] 36x = 36
</span></span>
// Solve equation [1] for the variable x
<span><span> [1] 36x = 36</span>
<span> [1] x = 1</span> </span>
// By now we know this much :
<span><span> x = 1</span>
<span> y = -13x/14-1/14</span></span>
<span>// Use the x value to solve for y
</span>
<span> y = -(13/14)(1)-1/14 = -1 </span>Solution :<span><span> {x,y} = {1,-1}</span>
<span>
Processing ends successfully</span></span>
Answer:
105
Step-by-step explanation:
First, you are going to convert dollars to cents. Since there are 100 cents in a dollar, multiple $20 by 100. Now you should have 2,000 cents. Now all you have to do is divide by 19, the cost of the stamps, and you should get 105.26. Because you can't by part of a stamp your answer would be 105.
21:3
9:3
3:1
there all a 3:1 ratio