Answer:
If we define the random variable X ="time spend by the students doign homework"
And we want to tes t is students spend more than 1 hour doing homework per night, on average (alternative hypothesis), so then the system of hypothesis for this case are:
Null hypothesis:
Alternative hypothesis:
And they wnat to use a sample size of n = 100 and a significance level of 0.05
Step-by-step explanation:
Previous concepts
A hypothesis is defined as "a speculation or theory based on insufficient evidence that lends itself to further testing and experimentation. With further testing, a hypothesis can usually be proven true or false".
The null hypothesis is defined as "a hypothesis that says there is no statistical significance between the two variables in the hypothesis. It is the hypothesis that the researcher is trying to disprove".
The alternative hypothesis is "just the inverse, or opposite, of the null hypothesis. It is the hypothesis that researcher is trying to prove".
Solution to the problem
If we define the random variable X ="time spend by the students doign homework"
And we want to tes t is students spend more than 1 hour doing homework per night, on average (alternative hypothesis), so then the system of hypothesis for this case are:
Null hypothesis:
Alternative hypothesis:
And they wnat to use a sample size of n = 100 and a significance level of 0.05
Answer: n = -198
Step-by-step explanation: To find n we need to work backwards, so we need to multiply -11 x 18 to get -198. So n would be -198.
Vertex: (-5,-2); parabola opens up;
General form of the equation for a vertical parabola opening up is:
y-k = a(x-h)^2; knowing that the vertex is at (-5,-2), we can write:
y+2 = a(x+5)^2. We need to find the value of the coefficient a.
From the graph we see that y is 10 when x is approx. -1 3/4 (or -7/4).
subst. these values into y+2 = a(x+5)^2, we get:
10 + 2 = a(-7/4 + 5)^2, or 12 = a(13/4)^2, or 1 = a(169/16).
Solving for a: a = 16/169 = 0.09, or approx 16/160, or 1/10. Unfortunately, this is not close to any of the four answer choices.
I thought it best to try again, and fortunately my second try was correct:
10+2 = a(13/4)^2, or (169/16)a. Thus, 12 = a(169/16)
12
Solving for a: a = ------------- = 1.14. The answer choice closest to this is 1.
169/16
Answer A is correct.
The answer is x = 4, y = -1 or (4, -1).
We are given :
- <u>2x + 7y = 1</u>
- <u>3x + 4y = 8</u>
<u />
Multiply the 1st equation with 3 and 2nd equation with 2.
<u>3. 3(2x + 7y) = 3(1) ⇒ 6x + 21y = 3</u>
<u>4. 2(3x + 4y) = 2(8) ⇒ 6x + 8y = 16</u>
<u />
Now, subtract : Equation 3 - Equation 4.
- 6x + 21y - 6x - 8y = 3 - 16
- 13y = -13
- y = -1
Substitute in the 1st equation.
- 3x + 4(-1) = 8
- 3x - 4 = 8
- 3x = 12
- x = 4
Answer:
3/10
Step-by-step explanation:
Bonnie has completed 0.5 + 0.2 = 0.7 of her art project. 1 - 0.7 = 0.3 of her art project remains to be completed.
_____
1/2 = 5/10 = 0.5
1/5 = 2/10 = 0.2