Given that Alberta Emery can sew 1 dress in 3 days. so the efficiency of Alverta Emery is given by,

Similarly, given that Allison Taylor takes 2 days to sew 1 dress, so the efficiency of Allison Taylor is given by,

When they combine their efforts, the amount of work done per day is given by,

So the number of days required to sew 30 dresses when both of them work together, is calculated as,

Thus, they will take 36 days to sew 30 dresses.