A Carload of Steel Rods Has Arrived at Cybermatic Construction

question 59

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 inches and a standard deviation of 0.05 inch, the probability that Claude's sample has a mean less than 119.985 inches is closest to _____________.

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