Answer:
<h3>
Step-by-step explanation:</h3>
The z-value is computed from ...
... z = (x -µ)/σ
... z = (184 -206)/10 = -2.2 . . . . for $184
... z = (200 -206)/10 = -0.6 . . . . for $200
You can look up these values in a normal distribution table, or you can use an appropriate calculator to find the corresponding percentiles.
... -2.2 corresponds to the 1.390 percentile. (That amount of area is below -2.2 standard deviations from the mean.)
... -0.6 corresponds to the 27.425 percentile.
Subtracting the two percentages gives the percentage of expenses between $184 and $200. That number is 26.035% ≈ 26%.
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<em>Comment on the calculator display</em>
The difference that got cut off from the display in the attachment is ...
... 0.2603496703
The <em>normalcdf( )</em> function requires a lower limit. Using -8 standard deviations is effectively equivalent to -∞ for this purpose, as any lower number has no effect on the least-significant digits of the result.
Answer:
1) one solution
2) Infinitely many solution
3) no solution
Step-by-step explanation:
The first equation is -14-8x=-2(-3x+7)
Let us expand the right hand side to get:
-14-8x=-2*-3x+-2*7
We multiply -14-8x=6x-14
We group similar terms to get:
-8x-6x=-14+14
Combine similar terms to get:
-14x=0
Divide through by -14 to get:
x=0
2) The second equation is 3+5x=5(x+2)-7
We expand to obtain:
3+5x=5x+5*2-7
Multiply to get:
3+5x=5x+10-7
This gives us
3+5x=5x+3
5x=5x
1=1
There is infinitely many solutions
3) The third equation is: 36-7x=-7(x-5)
We expand to get:
36-7x=-7x+35
Group similar terms;
-7x+7x=35-36
0=-1
This statement is not true so there is no solution.
Even functions (like this one) are symmetric to the y-axis. So even if you reflect it over the y-axis it will look the same :)