Question

Use the data in the following​ table, which lists​ drive-thru order accuracy at popular fast food chains. Assume that orders are randomly selected from those included in the table. ​Drive-thru Restaurant A B C D Order Accurate 322 269 231 141 Order Not Accurate 36 57 39 18 If one order is​ selected, find the probability of getting an order from Restaurant A or an order that is accurate. Are the events of selecting an order from Restaurant A and selecting an accurate order disjoint​ events? The probability of getting an order from Restaurant A or an order that is accurate is nothing. ​(Round to three decimal places as​ needed.)

Answer 1

Total order = 322 + 269 + 231 + 141 + 36 + 57 + 39 + 18 = 1113

P(order is from restaurant A or order is accurate) = P(order is from restaurant A) + P(order is accurate) - P(order is from restaurant A and order is accurate)

                                          = (322+36)/1113 + (322 + 269 + 231 + 141)/1113 - 322/1113

                                          = 0.898 (ans)

P(order is from restaurant A and order is accurate) = 322/1113 = 0.289

Since P(order is from restaurant A and order is accurate) is not equal to zero, they are not disjoint events.