If a choir consists of 2 boys and 4 girls, in how many ways can the singers be arranged in a row, so that all the boys are together? Do not differentiate between arrangements that are obtained by swapping two boys or two girls.  Choose the correct choice from the following answers
A) 120  B) 30  C) 24  D) 11  E) 5
There are 5 possibilities:   bbgggg   gbbggg   ggbbgg   gggbbg   ggggbb   Think of all 2 boys as a single unit. Together with 4 girls it makes a total of 5 units. The difference between the arrangements is the position of the boys (as a single unit). So the problem reduces to finding the number of unique patterns generated by changing the position of the boys who can occupy 1 of 5 available positions. If the number of available unique positions is 5, then the number of unique patterns equals 5 as well.   Answer: 5.
<result>E</result>
If a choir consists of 2 boys and 4 girls, in how many ways can the singers be arranged in a row, so that all the boys are together? Do not differentiate between arrangements that are obtained by swapping two boys or two girls.