The Mean Life of a Pair of Shoes Is 40

question 35

Multiple Choice

The mean life of a pair of shoes is 40 months with a standard deviation of 8 months.If the life of the shoes is normally distributed,how many pairs of shoes out of one million will need replacement before 36 months?

• A) 500,000
• B) 808,500
• C) 191,500
• D) 308,500

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Definitions:

Concentric Lamellae

Layers of bony matrix in an osteon, circularly arranged around a central canal containing blood vessels and nerves in the bone.

Trabeculae

Trabeculae are the small, beam-like structures of spongy bone, providing structural support and helping to reduce the weight of the skeleton.

Compact Bone

Bone that is denser and has fewer spaces than cancellous bone.

Osteocyte

A mature bone cell, derived from osteoblasts, embedded in bone matrix and involved in the maintenance of bone tissue.