A quality control engineer at a potato chip company tests the bag filling machine by weighing bags of potato chips. Not every bag contains exactly the same weight. But if more than 11% of bags are over-filled then they stop production to fix the machine. They define over-filled to be more than 1 ounce above the weight on the package.

The engineer weighs 138 bags and finds that 29 of them are over-filled. He plans to test the hypothesesH

0

: p = 0.11 versusH

a

: p > 0.11. What is the test statistic?

z =