An internet supplier of refilled ink cartridges for ink jet printers sold cartridges to 30,000 customers over the past two months. A random sample of 1000 of those customers revealed that 180 were not happy with their purchase. The margin of error was 2%. What range is likely to contain the population parameter?
A) 29,000 to 31,000
B) 16% to 20%
C) 160 to 200
D) 4800 to 6000

Question

Quizplus · Accepted Answer

The sample proportion of unhappy customers is 18% (180 out of 1000). With a margin of error of 2%, the range for the population proportion is 16% to 20%.

An Internet Supplier of Refilled Ink Cartridges for Ink Jet