Assignment:
A maintenance engineer has been approached by a supplier who promises less downtime for machines using its new molybdenum-based super lubricant. Of 120 machines maintained with the new lubricant, only 20% were out of service for more than an hour during the month of the test, while 30% of the 100 machines using the previous lubricant were down for more than an hour. Using the 0.05 level in an appropriate test, evaluate the supplier’s contention. Using the appropriate statistical table, what is the approximate p-value for this test?
Provide complete and step by step solution for the question and show calculations and use formulas.