The Expected (Mean)life of a Particular Type of Light Bulb

question 53

Multiple Choice

The expected (mean) life of a particular type of light bulb is 1,000 hours with a standard deviation of 50 hours.The life of this bulb is normally distributed.Which most closely reflects the probability that a randomly selected bulb would last fewer than 940 hours?

• A)0.3849
• B)0.8849
• C)0.1151
• D)0.6151
• E)0.6563

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Definitions:

Transfer Device

An aid or piece of equipment designed to assist in moving a person from one position or location to another.

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A type of injury to the skin and underlying tissue characterized by full-thickness skin loss that may expose some fat, but not muscle or bone.

Low-Air-Loss Therapy

A treatment method involving the use of specialized mattresses or supports that utilize airflow to reduce skin pressure and promote wound healing.

Dakin's Solution

An antiseptic solution containing sodium hypochlorite, used in wound care to kill bacteria and clean infections.