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: Find the absolute extrema of the function f(x) = x^3 - 6x^2 + 9x + 3 on the interval [0, 5].
+
Math question: What is the maximum value of the function f(x) = x^3 - 6x^2 + 9x - 2 on the interval [0, 4]?
+
What is the sign of equality for two triangles with corresponding sides of lengths 4, 8, and 10?
+
New questions in Mathematics
The strength of Kefexin oral suspension is 100 mg/ml. Nora has been prescribed cefalexin at a dose of 50 mg/kg/day divided in two single doses. Nora weighs 14 kg. How many milliliters of solution for Nora should be given as a single dose?
-11+29-18
STUDENTS IN A CLASS LEARN ONLY ONE FOREIGN LANGUAGE. two-sevenths of the students learn German, half of the students learn Spanish, and the remaining six students learn Italian. what is the number of students in this class? detail your reasoning carefully.
3x+5y=11 2x-3y=1
4.2x10^_6 convert to standard notation
What will be the density of a fluid whose volume is 130 cubic meters contains 16 technical units of mass? If required Consider g=10 m/s2
Determine the general equation of the straight line that passes through the point P (2;-3) and is parallel to the straight line with the equation 5x – 2y 1 = 0:
What is 28 marks out of 56 as a percentage
Suppose you have a sample of 100 values from a population with mean mu = 500 and standard deviation sigma = 80. Given that P(z < −1.25) = 0.10565 and P(z < 1.25) = 0.89435, the probability that the sample mean is in the interval (490, 510) is: A)78.87% B)89.44% C)10.57% D)68.27%
The sum of two numbers is 144. Double the first number minus thrice the second number is equal to 63. Determine the first two numbers.
A warehouse employs 23 workers on first​ shift, 19 workers on second​ shift, and 12 workers on third shift. Eight workers are chosen at random to be interviewed about the work environment. Find the probability of choosing exactly five first ​-shift workers.
Estimate the quotient for 3.24 ÷ 82
A machine produces 255 bolts in 24 minutes. At the same rate, how many bolts would be produced in 40 minutes?
From 1975 through 2020 the mean annual gain of the Dow Jones Industrial Average was 652. A random sample of 34 years is selected from this population. What is the probability that the mean gain for the sample was between 400 and 800? Assume the standard deviation is 1539
2)A tourist has 15 pairs of pants in his hotel room closet. Suppose 5 are blue and the rest are black. The tourist leaves his room twice a day. He takes a pair of pants and puts them on, the tourist leaves the first pair of pants in the closet again and takes another one and puts them on. What is the probability that the two pants chosen are black?
-1%2F2x-4%3D18
X^3 - x^2 - 4 = 0, what are the values of x?
x²-7x+12=0
How much does 7.2 moles of ammonium dichromate weigh? (NH4)2Cr2O7
5a-3.(a-7)=-3