Answer:
Step-by-step explanation:
We would set up the hypothesis test. This is a test of a single population mean since we are dealing with mean
For the null hypothesis,
µ = 17
For the alternative hypothesis,
µ < 17
This is a left tailed test.
Since the population standard deviation is not given, the distribution is a student's t.
Since n = 80,
Degrees of freedom, df = n - 1 = 80 - 1 = 79
t = (x - µ)/(s/√n)
Where
x = sample mean = 15.6
µ = population mean = 17
s = samples standard deviation = 4.5
t = (15.6 - 17)/(4.5/√80) = - 2.78
We would determine the p value using the t test calculator. It becomes
p = 0.0034
Since alpha, 0.05 > than the p value, 0.0043, then we would reject the null hypothesis.
The data supports the professor’s claim. The average number of hours per week spent studying for students at her college is less than 17 hours per week.
Answer:
x = -4, 10
Step-by-step explanation:
We take the square root and use the fact of "plus-minus" and find two values of x. The process of solving this equation is shown below:





Hence the two values of x are -4 and 10
Note: both (-7)^2 and (7)^2 are 49 . So we took "plus-minus" values of 
#a
We need Opposite/Hypotenuse i.e sin
All will be same


#c
Answer:
78%, no he didn't score high enough
Step-by-step explanation:
Answer:
7/20
Step-by-step explanation:
So first we know that there are a total od 25 students
15+10=25
And the probability of choosing the first girl is 15/25 or 3/5 simpler terms.
Now to be able to choose another girl in a row just multiply the then probability
So we started off with 25, if a girl was choosen, the population would b 24
and with 24, there is a missing girl so instead of 15 it is 14
now 14/24 or 7/12 simplified
multiply the two
7/12*3/5=21/60
Simplified
7/20