Consider the following premises. It is overcast if and only if Patricia is a taxi driver. If Patricia were a taxi driver, then it is late. If it is late, then Patricia is a taxi driver. It is not overcast. Can we infer the following from them? It is late.
 From the fact that if it is late, then Patricia is a taxi driver, and that if Patricia were a taxi driver, then it is late we can infer that it is late if and only if Patricia is a taxi driver. From the fact that it is overcast if and only if Patricia is a taxi driver we can infer that if Patricia were a taxi driver, then it is overcast. From the fact that if Patricia were a taxi driver, then it is overcast, and that it is not overcast we can infer that Patricia is not a taxi driver. Finally, from the fact that it is late if and only if Patricia is a taxi driver, and that Patricia is not a taxi driver we can infer that it is not late, which contradicts that It is late. Therefore, the answer is no.