4 boys and 2 girls are to be seated in a row in such a way that two girls are always together. In how many different ways can they be seated?

Assume the 2 girl students to be together i,e (one). Now there are 5 students.
Possible ways of arranging them are 5! = 120
Now they (two girl) can arrange themselves in 2! ways.
Hence, total ways = 120 x 2! = 240