Answer:
The standard deviation has changed for the worse
Step-by-step explanation:
We need to compare the sample standard deviation of 52.3 to the known population standard deviation of 43.7. The test we will use will use Chi-Square distribution...
The hypothesis for this test are...
H0: σ = 43.7
Ha: σ ≠ 43.7
This is a 2 tailed test.
We have n = 81
s = 52.3
s² = 52.3² = 2735.29
σ = 43.7
σ² = 1909.69
The degrees of freedom are: n - 1, in this case, 80
Our significance level is 95%, so our critical values are
Χ² < 57.153 and Χ² > 106.629
The test static is found with the formula:
Χ² = [(n - 1)s²]/σ²
Plug in what we have and find the test stastic....
Χ² = [80(2735.29)]/1909.69
Χ² = 114.586
114.586 > 106.629, we reject the null hypothesis. There is evidence that shows that the standard deviation has changed. The evidence suggests that it has increased, which would make the new method worse than the old method.
Answer:
3 cycles
Step-by-step explanation:
in one period, you have one full cycle
because the period for this function is 4pi, you have one cycle per 4pi
if you have a total of 12pi, you would have 3 cycles (12pi/4pi=3)
hope this helps!
Answer:I don’t write English you should translate
Áp dụng tính chất của đường trung bình ta có:
20+x=2.(2x+22)
20+x=4x+44
X-4.x=44-20
-3.x=24
X=24/-3x=-8
Trong độ dài ko có độ âm nên tất cả đại lượng hình học đều mang dấu (+) vì vậy kết quả cuối cùng sẽ là 8
Step-by-step explanation:
Answer:
Hello Mate! Ans : Yes, number x = 9.688888...... is rational number.