Answer:
0.9544
Step-by-step explanation:
P(-2 < Z < 2) means that Z has mean 0 and standard deviation 2.
P(−2 < Z < 2) = F(2) - F(-2)
Using the Z - table,
F(2) = 0.9772
and F(-2) = 0.0228
Thus,
P(−2 < Z < 2) = 0.9772 - 0.0228 = 0.9544
This means that data within two standard deviation is 95%.
Answer:
Sadie took 47 minutes to finish her test.
Step-by-step explanation:
Let Laura's time be x minutes.
Then we have:
x + 3x - 16 = 68
4x = 84
x = 21 minutes.
So Sadie took 3(21) - 16 = 63-16
= 47 minutes.
You would either start at 0 and go over 235 then you would go over 123 more
Answer: 43 degrees
Explanation: All of the angles inside of a triangle add to equal 180 degrees. All you have to do is subtract the two angle measures from 180 degrees to get the answer.
180-90-47=43 degrees
Answer:
(22.12, 27.48)
Step-by-step explanation:
Given : Significance level : 
Sample size : n= 8 , which is a small sample (n<30), so we use t-test.
Critical values using t-distribution: 
Sample mean : 
Standard deviation : 
The confidence interval for population means is given by :-

i.e. 

Hence, the 95% confidence interval, assuming the times are normally distributed.= (22.12, 27.48)