<h3>
Answer: 8.323 (approximate)</h3>
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Explanation:
s = 32 = sample standard deviation
n = 40 = sample size
Despite not knowing the population standard deviation (sigma), we can still use the Z distribution because n > 30. When n is this large, the student T distribution is approximately the same (more or less) compared to the standard Z distribution. The Z distribution is nicer to work with.
At 90% confidence, the z critical value is roughly z = 1.645. This can be found using either a Z table or a calculator.
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We have these values:
- z = 1.645 (approximate)
- s = 32
- n = 40
Plug these values into the margin of error formula.
The margin of error is roughly 8.323
I rounded to 3 decimal places because z = 1.645 is rounded to 3 decimal places. If your teacher wants some other level of precision, then be sure to follow those instructions.
Answer:
A is correct because there are only 2 sides to flip to, giving it a probability of 0.50, or 1/2 that they will lands heads up.
We can solve this problem using discriminant.
x^2-4x-12's discriminant is
(-4)^2-4*-12=16+48 which is clearly larger than 0
This means that it crosses over the axes 2 times.
In case you don't know what discriminant is, its in equation ax^2+bx+c
the discriminant is b^2-4ac.
If its positive it has 2 crosses with x axis, if negative then 0 crosses, if 0 then 1 cross.
Hope this helped at least a little bit :D
Answer:
The amount invested at 15% = $257.14
The amount invested at 8% = $942.86
Step-by-step explanation:
Let the amount invested at:
15% = a
8% = b
Total invesment = $1200
Hence:
a + b= $1200....... Equation 1
a = 1200 - b
15% × a + 8% × b = 9.5% × 1200
0.15a + 0.08b = 0.095 × 1200
0.15a + 0.08b = 114..... Equation 2
We substitute 1200 - b for a in Equation 2
0.15(1200 - b) + 0.08b = 114
180 - 0.15b + 0.08b = 114
- 0.15b + 0.08b = 114 - 180
- 0.07b = - 66
b = -66/-0.07
b = $942.85714286
Approximately = $942.86
Note that:a = 1200 - b
a = $1200 - $942.86
a = $257.14
Solve for the first variable in one of the equations, then substitute the result into the other equation.
Point Form:
(3, 0)
Equation Form:
x = 3, y = 0