CR7.10 The Cedar Rapids Gazette (November 20, 1999)

reported the following information on compliance with child restraint laws for cities in Iowa:

City Number of Children Observed Number Properly Restrained Cedar Falls 210 173 Cedar Rapids 231 206 Dubuque 182 135 Iowa City (city) 175 140 Iowa City (interstate) 63 47

a. Use the information provided to estimate the following probabilities:

i. The probability that a randomly selected child is properly restrained given that the child is observed in Dubuque.

ii. The probability that a randomly selected child is properly restrained given that the child is observed in a city that has “Cedar” in its name.

b. Suppose that you are observing children in the Iowa City area. Use a tree diagram to illustrate the possible outcomes of an observation that considers both the location of the observation (city or interstate) and whether the child observed was properly restrained.