Neco 2022 Christian Religious Studies Question 39

Paul made three missionary journeys. In the first journey he visited \(6\) cities, founding one church in each. In the second journey he visited twice as many cities as in the first, but in two of those cities the existing churches merged, reducing the net new churches by \(2\). In the third journey he visited a number of cities equal to the total number of letters he wrote (\(13\)) plus the number of his companions on that journey. In each city of the third journey he founded two churches, except in the city where he stayed for six months, where he founded only one. If the total number of churches founded by Paul across all journeys is \(45\), how many cities did he visit on the third journey?