Two classmates have decided to read all the volumes in a popular series of books. Mary has already read 4 volumes and will continue to read new ones at a rate of 2 volumes per week. Eva, who hasn't started reading the series yet, will read 3 volumes per week. At some point, Eva will catch up with Mary and they will be reading the same book. How long will that take? How many volumes will each girl have read by then?