Answer:
z-test.
Step-by-step explanation:
We want to perform an hypothesis test for a population mean.
In the case that the <u>standard deviation of the population is known</u> and the population distribution is normal, even if the sample is small, <u>we will use a z-test</u>.
The usual case is to not know the standard deviation of the population, in which case a t-test is adequate instead of a z-test, taking into account the degrees of freedom of the sample.
Think:
7:55 a.m. is 5 minutes (5/60 hrs) before 8 a.m.;
from 8 to noon it's 4 hours, and from noon to 2:40 p.m. is 2 2/3 hours.
Thus, you're in school 5/60 hrs + 4 hrs + 2 2/3 hrs, or
6 2/3 hrs + 5/60 hrs, or 6 40/60 hrs + 5/60 hrs, or
6 45/60 hrs, or 6 3/4 hrs.
Of course there are other ways in which you could do this problem:
4 hrs 5 min plus 2 hrs 40 min comes out to 6 hrs 45 min, or 6 3/4 hrs.
Answer:
b
Step-by-step explanation:
B. Y= (x - 10) ^ 4 - 81 OR y = x^4 - 20x +91
15:4.
Step-by-step explanation:
1 hour = 60 min
3 hours = 60 x 3 = 180 min
Ratio:
180/48
Simplest form 15/4
Therefore, the simplest form of the ratio will be 15:4
<span> 1/8,2/16,3/24 that should be the answer </span>