Question

You collect a random sample of 50 children and compute , the average height in inches. The sample standard deviation (s) equals 10. Suppose the true mean height μ equals 45 inches. For which of the following values of will a 95% confidence interval contain the true mean μ? I. = 47.5 inches II. = 50 inches III. = 42 inches

123

likes
613 views

Answer to a math question You collect a random sample of 50 children and compute , the average height in inches. The sample standard deviation (s) equals 10. Suppose the true mean height μ equals 45 inches. For which of the following values of will a 95% confidence interval contain the true mean μ? I. = 47.5 inches II. = 50 inches III. = 42 inches

Expert avatar
Birdie
4.5
104 Answers
We can use the formula for a confidence interval:

Confidence Interval = \bar{x} \pm z \times \frac{s}{\sqrt{n}},

where:
\bar{x} is the sample mean,
z is the Z-value for the desired confidence level (95% in this case),
s is the sample standard deviation,
n is the sample size.

Given values:
\bar{x} = \mu = 45 inches,
s = 10 inches,
n = 50 children,
For 95% confidence level, the Z-value is 1.96 (you can refer to Z-table for this value).

Plugging in these values we get:

I. CI_{I} = 47.5 \pm 1.96 \times \frac{10}{\sqrt{50}},

II. CI_{II} = 50 \pm 1.96 \times \frac{10}{\sqrt{50}},

III. CI_{III} = 42 \pm 1.96 \times \frac{10}{\sqrt{50}}.

Calculating these confidence intervals gives:

I. CI_{I} = 47.5 \pm 2.78,
II. CI_{II} = 50 \pm 2.78,
III. CI_{III} = 42 \pm 2.78.

Only the 95% confidence interval for I. contains the true mean height 45 inches.

\boxed{\text{Answer: I. } \mu = 47.5 \text{ inches}}

Frequently asked questions (FAQs)
Math question: What is the derivative of the function f(x) = ∫(2x^3 - 4x) dx from x = 1 to x = 3?
+
Math question: What is the limit of (3x + 2) as x approaches 4?
+
Math Question: What is the simplified expression of log(base b) 1 + log(base b) x - log(base b) y?
+
New questions in Mathematics
2.5 / 21.85
The miles per gallon (mpg) for each of 20 medium-sized cars selected from a production line during the month of March are listed below. 23.0 21.2 23.5 23.6 20.1 24.3 25.2 26.9 24.6 22.6 26.1 23.1 25.8 24.6 24.3 24.1 24.8 22.1 22.8 24.5 (a) Find the z-scores for the largest measurement. (Round your answers to two decimal places.) z =
4. Show that if n is any integer, then n^2 3n 5 is an odd integer
If the midpoint of point A on the x=3 line and point B on the y=-2 line is C(-2,0), what is the sum of the ordinate of point A and the abscissa of point B?
41/39 - 1/38
-3(-4x+5)=-6(7x-8)+9-10x
What is 28 marks out of 56 as a percentage
The cost of unleaded gasoline in the Bay Area once followed an unknown distribution with a mean of $4.59 and a standard deviation of $0.10. Sixteen gas stations from the Bay Area are randomly chosen. We are interested in the average cost of gasoline for the 16 gas stations. 84. Find the probability that the average price for 30 gas stations is less than $4.55. a 0.6554 b 0.3446 c 0.0142 d 0.9858 e 0
Two business partners have a bank balance of $17,942.00. After the first year their interest brings their balance to $18,928.91. What rate of interest is earned?
form a key for your lock containing the numbers 2 2 5 8 How many different keys can you form?
A person decides to invest money in fixed income securities to redeem it at the end of 3 years. In this way, you make monthly deposits of R$300.00 in the 1st year, R$400.00 in the 2nd year and R$500.00 in the 3rd year. Calculate the amount, knowing that compound interest is 0.6% per month for the entire period. The answer is 15,828.60
Use the power rule for logarithms to solve the following word problem exactly. If you invest $1, 000 at 5% interest compounded annually, how many years will it take before you have $2,000?
(2m+3)(4m+3)=0
What is 75 percent less than 60
-1%2F2x-4%3D18
ind the z-score for which 72% of the distribution's area lies between -z and z. -1.7417, 1.7417 -1.1538, 1.1538 -1.0803, 1.0803 -2.826, 2.826
Calculate the difference between 407 and 27
Cuboid containers (open at the top) should be examined with regard to their volume. The figure below shows a network of such containers (x ∈ Df). Determine a function ƒ (assignment rule and definition area D) that describes the volume of these containers and calculate the volume of such a container if the content of the base area is 16 dm². Show that this function f has neither a local maximum nor a global maximum
y’’ -4y’ +4y = (12x^2 -6x)e^2x Y(0)= 1 Y’(0)=0 Y(x)=c1y1+c2y2+yp
f(r) = 1/r+9 find f(x^2) + 1