One rainy Saturday morning, Adam woke up to hear his mom complaining about the house being dirty. "Mom is always grouchy when it rains," Adam's brother said to him. Adam decided to figure out if this statement was actually true. For the next year, he charted every time it rained and every time his mom was grouchy. He found that rainy days and his mom being grouchy were entirely independent events. Some of his data are shown in the table below.