The manufacturer of the ColorSmart-5000 television set claims 95 percent of its sets last at least...

The manufacturer of the ColorSmart-5000 television set claims 95 percent of its sets last at least five years without needing a single repair. In order to test this claim, a consumer group randomly selects 400 consumers who have owned a ColorSmart-5000 television set for five years. Of these 400 consumers, 316 say their ColorSmart-5000 television sets did not need a repair, whereas 84 say their ColorSmart-5000 television sets did need at least one repair.

(a) Find a 99 percent confidence interval for the proportion of all ColorSmart-5000 television sets that have lasted at least five years without needing a single repair. (Round your answers to 3 decimal places.)

The 99 percent confidence interval is [, ].

(b) Does this confidence interval provide strong evidence that the percentage of all ColorSmart- 5000 television sets that last at least five years without a single repair is less than the 95 percent claimed by the manufacturer?

(Click to select)NoYes , the interval is (Click to select)belowabove .95.

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orchestra answered 1 year ago

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