Answer:
21.9 ft
Step-by-step explanation:
The area of a square is the square of the side length, so the side length is the square root of the area:
... s = √(479 ft²) ≈ 21.886 ft
This is approximately 21.9 ft.
Given:
n = 20, sample size
xbar = 17.5, sample mean
s = 3.8, sample standard deiation
99% confidence interval
The degrees of freedom is
df = n-1 = 19
We do not know the population standard deviation, so we should determine t* that corresponds to df = 19.
From a one-tailed distribution, 99% CI means using a p-value of 0.005.
Obtain
t* = 2.8609.
The 99% confidence interval is
xbar +/- t*(s/√n)
t*(s/√n) = 2.8609*(3.8/√20) = 2.4309
The 99% confidence interval is
(17.5 - 2.4309, 17.5 + 2.4309) = (15.069, 19.931)
Answer: The 99% confidence interval is (15.07, 19.93)
Answer:
The appropriate probability model for X is a Binomial distribution,
X
Bin (<em>n</em> = 5, <em>p</em> = 1/33).
Step-by-step explanation:
The random variable <em>X</em> can be defined as the number of American births resulting in a defect.
The proportion of American births that result in a birth defect is approximately <em>p</em> = 1/33.
A random sample of <em>n</em> = 5 American births are selected.
It is assumed that the births are independent, i.e. a birth can be defective or not is independent of the other births.
In this experiment the success is defined as a defective birth.
The random variable <em>X</em> satisfies all criteria of a Binomial distribution.
The criteria are:
- Number of observations is constant
- Independent trials
- Each trial has only two outcomes: Success and Failure
- Same probability of success for each trial
Thus, the appropriate probability model for X is a Binomial distribution, Bin (<em>n</em> = 5, <em>p</em> = 1/33).
Answer:
x=7
Step-by-step explanation:
To set up for this answer, we need to set it up as an equation: 2x+12=5x-9.
get the xs on one side and the whole numbers on the other.
that leaves you with 21=3x.
divide by 3 on both sides to get the answer of x=7
Answer: x=0.4
Step-by-step explanation:
0.5x + 4+0.9x = x+5
1.4x-x= +1
0.4x=1
X=0.4
Hope this helps