In a certain sporting goods manufacturing company, a quality control expert tests a randomly selected group of 1,000 tennis balls in order to determine how many contain defects. If this quality control expert discovered that 13 of the randomly selected tennis balls were defective, which of the following inferences would be most supported?
A. 98.7% of the company's tennis balls are defective
B. 98.7% of the company's tennis balls are not defective
C. 9.87% of the company's tennis balls are defective
D. 9.87% of the company's tennis balls are not defective
Answer:B
In a certain sporting goods manufacturing company, a quality control expert tests a randomly selected group of 1,000 tennis balls in order to determine how many contain defects. If this quality control expert discovered that 13 of the randomly selected tennis balls were defective, which of the following inferences would be most supported?
A. 98.7% of the company's tennis balls are defective B. 98.7% of the company's tennis balls are not defective C. 9.87% of the company's tennis balls are defective D. 9.87% of the company's tennis balls are not defective
Explanation: B The quality control expert discovered that 13 out of 1,000 randomly selected tennis balls were defective. = 0.013, which is equivalent to 1.3%. This means that 100 - 1.3 = 98.7% of tennis balls tested were not defective, and this data most supports answer (B).