A metallurgist has invented a new tungsten alloy for use in the filaments of light bulbs...

A metallurgist has invented a new tungsten alloy for use in the filaments of light bulbs that is supposed to burn brighter with the use of less energy. A company investigates the potential costs of producing the new type of bulb and decides that production would be economically feasible if the bulbs would last an average of longer than 2000 hours in continuous usage. Twenty-five of the new bulbs are tested and found to last an average of 2240 hours with a standard deviation of 600 hours. Is this strong evidence that the average life of all such bulbs is higher than 2000 hours? Translate this into a statistical hypothesis-testing problem and carry out the test. Be sure to give the null and alternative hypotheses, the value of the test statistic, the p-value, and your conclusions.

Expert Solution

orchestra answered 2 years ago

Calculate the atomic percent of tungsten in an alloy prepared with 56 grams of tungsten and...

Calculate the atomic percent of tungsten in an alloy prepared with 56 grams of tungsten and 48 grams of aluminum. The atomic mass of tungsten is 183.85 g/mol and aluminum is 26.98 g/mol.

A new LED light to replace incandescent bulbs has come on the market. The box says...

A new LED light to replace incandescent bulbs has come on the market. The box says it has an average life of 9,000 hours with a standard deviation of 300 hours. a) What is the probability that a single bulb will last between 8950 and 9100 hours? b) What is the probability that the mean of a sample of 70 bulbs picked at random will be between 8950 and 9100 hours?

A company manufactures light bulbs. These light bulbs have a length of life that is normally...

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A box contains six 25-watt light bulbs, nine 60-watt light bulbs, and five 100-watt light bulbs....

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A company that manufactures light bulbs claims that its light bulbs last an average of 1500...

A company that manufactures light bulbs claims that its light bulbs last an average of 1500 hours. A consumer research group wants to test the hypothesis that the mean life of light bulbs manufactured by this company is less than 1500 hours. A sample of 35 light bulbs manufactured by this company gave a mean life of 1450 hours with a standard deviation of 100 hours. The significance level of the hypothesis test is 5% and the distribution for the...

A manufacturer of light bulbs claims that its light bulbs have a mean life of 1520...

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5. A shipment of 50 light bulbs contains 10 defective light bulbs. In order to test...

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A manufacturer of light bulbs claims that the average lifetime of one of their bulbs is...

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A circuit for light bulbs in a car has a battery with a terminal voltage of...

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Two light bulbs are 1.00 mapart. From what distance can these light bulbs be marginally resolved...

Two light bulbs are 1.00 mapart. From what distance can these light bulbs be marginally resolved by a small telescope with a 3.90 cm-diameter objective lens? Assume that the lens is diffraction limited and λ=600nm.

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