4. Construct a 95% confidence interval of the true mean life span of LED light bulbs manufactured by this factory.
Percentage
A percentage is a number indicated as a fraction of 100. It is a dimensionless number often expressed using the symbol %.
Algebraic Expressions
In mathematics, an algebraic expression consists of constant(s), variable(s), and mathematical operators. It is made up of terms.
Numbers
Numbers are some measures used for counting. They can be compared one with another to know its position in the number line and determine which one is greater or lesser than the other.
Subtraction
Before we begin to understand the subtraction of algebraic expressions, we need to list out a few things that form the basis of algebra.
Addition
Before we begin to understand the addition of algebraic expressions, we need to list out a few things that form the basis of algebra.
Answer 4,5&6
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Question
A factory manufacturing light emitting diode LED bulbs claims that their light bulbs last
for 50,000 hours on the average. To confirm if this is valid, a quality control manager obtained a
sample of 50 LED light bulbs and got a mean lifespan of 40,000 hours. The standard deviation of
the manufacturing process is 1000 hours.
1. What is the best point estimate for the true mean life span of the LED light bulbs
manufactured by this factory.
A factory manufacturing light emitting diode LED bulbs claims that their light bulbs last
for 50,000 hours on the average. To confirm if this is valid, a quality control manager obtained a
sample of 50 LED light bulbs and got a mean lifespan of 40,000 hours. The standard deviation of
the manufacturing process is 1000 hours.
1. What is the best point estimate for the true mean life span of the LED light bulbs
manufactured by this factory.
2. What is the standard error of this point estimate?
3. What is the margin of error of this point estimate?
4. Construct a 95% confidence interval of the true mean life span of LED light bulbs
manufactured by this factory.
5. Do you think that the claim of the manufacturer is valid? Explain.
6. If you want to be 99% confident that the point estimate is at most 100 hours from the true
mean life span, how many light bulbs should be included in the sample?
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content:
A factory manufacturing light emitting diode LED bulbs claims that their light bulbs last
for 50,000 hours on the average. To confirm if this is valid, a quality control manager obtained a
sample of 50 LED light bulbs and got a mean lifespan of 40,000 hours. The standard deviation of
the manufacturing process is 1000 hours.
1. What is the best point estimate for the true mean life span of the LED light bulbs
manufactured by this factory.
2. What is the standard error of this point estimate?
3. What is the margin of error of this point estimate?
4. Construct a 95% confidence interval of the true mea
life span of LED light bulbs
manufactured by this factory.
5. Do you think that the claim of the manufacturer is valid? Explain.
6. If you want to be 99% confident that the point estimate is at most 100 hours from the true
mean life span, how many light bulbs should be included in the sample?](/v2/_next/image?url=https%3A%2F%2Fcontent.bartleby.com%2Fqna-images%2Fquestion%2F688c6eb9-28f3-4bad-b8f2-f8f5cb0180a4%2Faed3813e-d35d-4c84-a26d-5bcda5eddc6b%2Fbs27l1_processed.jpeg&w=3840&q=75)
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