Elderly wheelchair user study. The American Journal of Public Health (Jan. 2002) reported on a study of elderly wheelchair users who live at home. A sample of 306 wheelchair users, age 65 or older, were surveyed about whether they had an injurious fall during the year and whether their home featured any one of five structural modifications: bathroom modifications, widened doorways/hallways, kitchen modifications, installed railings, and easy-open doors. The responses are summarized in the accompanying table. Suppose we select, at random, one of the 306 wheelchair users surveyed.
a. Find the probability that the wheelchair user had an injurious fall.
b. Find the probability that the wheelchair user had all five features installed in the home.
c. Find the probability that the wheelchair user had no falls and none of the features installed in the home.
d. Given no features installed in the home, find the probability of an injurious fall.