Parisukat Light Manufacturing Company provided estimates of the light expectancy of their newly manufactured LED LITES in their brochures. A single random sample LED LITES shows the following useful...

ANSWERS SHOULD BE IN 4 DECIMAL PLACES

Extracted text: Parisukat Light Manufacturing Company provided estimates of the light expectancy of their newly manufactured LED LITES in their brochures. A single random sample LED LITES shows the following useful life in thousand hours: 55, 70, 52, 65, 75, 85, 45, 50, 75 Find: a. Mean useful life, µ: b. Standard deviation of the useful life, ơ: