needs to be answered ASAP please

Question

harry needs to write christmas cards, however he can only write lists in these 2 ways

 

girl                 boy

boy                girl

girl                 boy

 

if there are 10 girls and 12 boys, how many possibilities of lists can he write?

Answer 1

Let's take the girl/ boy /girl list  He has any of 10 girls to put first  and then any of 12 boys to put second  and then any of 9 girls to put 3rd.  This results in 10 x 12 x 9  =  1080 ways to write girl,boy,girl

 

If  we look at boy/girl/boy , we have 12 x 10 x 11  = 1320 ways to write the list this way.

 

Adding the two ways together we get 1080  +  1320  =  2400 Seems like to nice a number not to be correct