Answer: 0.0304
Step-by-step explanation:
A z-test is a statistical test that is used to determine if two population means are different when the variances are known and the sample size is large. The test statistic is assumed to have a normal distribution, and nuisance parameters such as standard deviation should be known in order for an accurate z-test to be performed.
A z-statistic, also known as z-score, is a number representing how many standard deviations above or below the mean population a score derived from a z-test is.
Therefore,
sample size,n = 36
mean,u = 16 ounce
standard deviation,s = 0.2 pounds = 3.2 ounce
x = 15 ounce
z = (x-u) / (s/sqrt(n)) = -1.875
In conclusion, the probability that the amount dispensed by box will be increased is:
P(X<15) = P(Z<-1.875)
= 1 - P(Z<1.875)
= 1 - 0.9696
0.0304
The Answer is 0.0304.
its spends 2.5 hours going 35 miles per hour. so the answer is 2.5 because 35 miles as you said goes 2.5 hours
Answer:
d.
Step-by-step explanation:
Hello!
The objective of this test is to know if aerobic exercise modifies hippocampus activity. A random sample of 120 elderly men and women was taken and divided into two groups.
Group 1: Walked around a track three times a week.
Group 2: Did a variety of less aerobic exercises, including yoga and resistance training with bands.
After a year their brains were scanned showing that group 1 had an increase of 2% in their hippocampus and group 2 showed a decrease of 1.4%
a. True, this type of observational study can be the prelude to a more formal statistical study.
b. True, the explanatory variable is "type of exercise", it's the variable that the investigator suspects influence the hippocampus volume.
c. True, the objective of this experiment is to test if there is any modification on hippocampus volume, that's why the volume of the hippocampus was measured, before and after a year of exercise.
d. False, this is an observational study, you cannot establish a causal relationship between the two variables. Just inform you that there seems to be an association. To be able to generalize the results to all elderly population you need a more formal statistical experiment to support your conclusions.
I hope it helps!
Answer:
this is the answer
Step-by-step explanation:
hope it helped!!!
There are a couple of ways to tackle this one, using the 45-45-90 rule or just using the pythagorean theore, let's use the pythagorean theorem.
the angle at A is 45°, and its opposite side is BC, the angle at C is 45° as well, and its opposite side is AB, well, the angles are the same, thus BC = AB.
hmmm le'ts call hmmm ohh hmmm say z, thus BC = AB = z.
