A Carload of Steel Rods Has Arrived at Cybermatic Construction

question 85

Multiple Choice

A carload of steel rods has arrived at Cybermatic Construction Company.The car contains 50,000 rods.Claude Ong, Manager of Quality Assurance, directs his crew to measure the lengths of 100 randomly selected rods.If the population of rods have a mean length of 120 centimetres and a standard deviation of 0.05 centimetres, the probability that Claude's sample has a mean less than 119.985 centimetres is ___.

• A)0.9974
• B)0.0026
• C)0.4987
• D)0.0013
• E)0.0030

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Definitions:

Gram-Negative Bacteria

Bacteria with cell walls consisting of a thin peptidoglycan layer and a thick outer membrane. Compare with gram-positive bacteria

Cyanobacteria

Photosynthetic bacteria that produce oxygen, found in aquatic and terrestrial environments, sometimes causing blooms.

Photosynthesis

The process by which green plants, algae, and some bacteria convert light energy into chemical energy in the form of glucose, using carbon dioxide and water.

Clostridia

A genus of bacteria, some species of which are pathogenic, known for their ability to produce spores and thrive in anaerobic conditions.