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
103 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)
What is the value of 3 raised to the power of 5?
+
What is the variant of the chain rule used to find the derivative of composite functions?
+
Math question: What is the derivative of f(x) = 3x^4 + 2x^3 - 5x^2 + 7x - 9?
+
New questions in Mathematics
Find the equation of the normal to the curve y=x²+4x-3 at point(1,2)
Derivative of x squared
Determine the momentum of a 20 kg body traveling at 20 m/s.
Divide 22 by 5 solve it by array and an area model
(-5/6)-(-5/4)
If f(x,y)=6xy^2+3y^3 find (∫3,-2) f(x,y)dx.
Convert 78 percent to a decimal
How many square feet of floor area are there in three two-storey apartment houses, each of which is 38 feet wide and 76 feet long?
89, ÷ 10
Solve the following equation for x in exact form and then find the value to the nearest hundredths (make sure to show your work): 5e3x – 3 = 25
Engineers want to design seats in commercial aircraft so that they are wide enough to fit ​95% of all males.​ (Accommodating 100% of males would require very wide seats that would be much too​ expensive.) Men have hip breadths that are normally distributed with a mean of 14.4 in. and a standard deviation of 1.2 in. Find P95. That​ is, find the hip breadth for men that separates the smallest ​95% from the largest 5​%.
Convert 5/9 to a decimal
TEST 123123+1236ttttt
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
2.380× (1+0.05) / 0.95−0.05
To find the increased amount on a standard term deposit with the following conditions: starting amount: BGN 13000, type of deposit: annual, annual compound interest rate: 1.4%, after 4 years;
At the end of a lively discussion within your study group, your class neighbor, for the relevance of your points of view, asks your opinion on the subject of their debate which is the following question Am I the slave of my unconscious? Solve the problem posed by this subject in an argumentative production.
A post office has three categories of letters: 60% are from businesses, 30% are individual mail, and the remaining 10% are government mail. 5% of the letters from businesses have address errors, 10% of the individual mail has address errors, while 1% of the government mail has address errors. If we receive a letter with an address error, what is the probability that it is individual mail?"
Find the rule that connects the first number to the second number of each pair. Apply the rule to find the missing number in the third pair. (18 is to 22) (54 is to 26) (9 is to ?)