Answer:
Step-by-step explanation:
Hello!
To test if boys are better in math classes than girls two random samples were taken:
Sample 1
X₁: score of a boy in calculus
n₁= 15
X[bar]₁= 82.3%
S₁= 5.6%
Sample 2
X₂: Score in the calculus of a girl
n₂= 12
X[bar]₂= 81.2%
S₂= 6.7%
To estimate per CI the difference between the mean percentage that boys obtained in calculus and the mean percentage that girls obtained in calculus, you need that both variables of interest come from normal populations.
To be able to use a pooled variance t-test you have to also assume that the population variances, although unknown, are equal.
Then you can calculate the interval as:
[(X[bar]_1-X[bar_2) ± 
* 
]
[(82.3-81.2) ± 1.708* (6.11*
]
[-2.94; 5.14]
Using a 90% confidence level you'd expect the interval [-2.94; 5.14] to contain the true value of the difference between the average percentage obtained in calculus by boys and the average percentage obtained in calculus by girls.
I hope this helps!
Answer:
Step-by-step explanation:
They are about 3 meters away from each other
and the correct area is 15.5-12 and the correct answer is 3.5 meters apart
The experimental units in this experiment are the 10 plants in group 2.
The experimental unit is a term used in science to refer to an individual or group of objects that are initially equivalent and then undergo experimental processes.
According to the above, the experimental unit of this experiment is the group 2 of plants because these are the plants that are going to be put into experimentation with a new fertilizer.
Then, the answer is D, because it refers to the experimental unit corresponding to this experiment.
Learn more in: brainly.com/question/17034824
Answer:
Step-by-step explanation:
Let x be the random variable. Since it is normally distributed and the population mean and population standard deviation are known, we would apply the formula,
z = (x - µ)/σ
Where
x = sample mean
µ = population mean
σ = standard deviation
From the information given,
µ = 474
σ = 32
x = 514
The probability of being below 514 is expressed as P(x < 514)
For x = 514,
z = (514 - 474)/32 = 1.25
Looking at the normal distribution table, the probability value corresponding to area below the z score is 0.89
Therefore,
P(x < 514) = 0.89
