Step-by-step explanation:
its .86 which is closer to .87
so choose the first one
Answer:
The answer tot he question provided is 25.
Answer: 20 ft
Step-by-step explanation:
The mirror is set away from the flagpole on the same scale set away from her.
The distance she stand's away from the mirror is 1/4 of the length of the distance between the mirror and the flag pole because she's 1/4 of the flagpole's size.
This means her size x4 is the size for the flag pole. This checks out because 12x4=48
So to find the height we must do 5x4
5x4=20
Answer:
15
Step-by-step explanation:
Math is fun.
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.