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

question 68

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.What is the probability that a randomly selected bulb would last fewer than 1100 hours?

• A) 0.4772
• B) 0.9772
• C) 0.0228
• D) 0.5228
• E) 0.5513

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Definitions:

Genetic instructions

The information encoded in an organism's DNA that guides growth, development, and function.

Fluid intelligence

The ability to think logically and solve problems in novel situations, independent of acquired knowledge.

Prospective memory

The aspect of memory that involves remembering to perform a planned action or intention at the appropriate time.

Retrospective memory

The ability to remember information and events from the past, including facts, experiences, and people.