Kyra Multiplied the number 56.8 by 10.
Answer:
[22.57 ± 2.776]
Step-by-step explanation:
Hello!
You have the 95% Confidence Z-interval (21.182;23.958), the mean X[bar]= 22.57 and the sample size n=25.
The formula for the Z interval is
[X[bar] ±
]
The value of Z comes from tha standard normal table:
![Z_{1-\alpha /2} = Z_{0.975}= 1.96](https://tex.z-dn.net/?f=Z_%7B1-%5Calpha%20%2F2%7D%20%3D%20Z_%7B0.975%7D%3D%201.96)
The semiamplitude (d) or margin of error (E) of the interval is:
E or d= (Upperbond- Lowerbond)/2 = (23.958-21.182)/2 = 2.776
[X[bar] ± E]
[22.57 ± 2.776]
I hope it helps!
<h3>
Answer: 17%</h3>
====================================================
Explanation:
The change in value is 30-25 = 5, so the amount has dropped by 5
Divide this change over the original amount to get 5/30 = 0.1667 approximately. This converts to 16.67% roughly, and that rounds to 17%
----------------
Here's a way to do it using a formula
A = old value = 30
B = new value = 25
C = percent change
C = [ (B-A)/A ] * 100%
C = [ (25-30)/30 ] * 100%
C = -0.1667 * 100%
C = -16.67%
C = -17%
The negative percent change means we have a percent decrease. The class size went down by about 17%.
240 people surveyed did not like any of the top three types of music.
Pretty sure it’s c sorry if wrong