Boys Vs Girls with Menti

Six boys and six girls sit in a row randomly. Find the probability that (i) the six girls sit together,(ii) the boys and girls sit alternately.

Five boys and five girls form a line with the boys and girls alternating.Find the number of ways of making the line.

The total number of ways in which 4 boys and 4 girls can form a line, with boys and girls alternating, is

The average weight of girls is 15 and the average weight of boys is 30 and the average weight of boys and girls both is 25. If the number of boys are 12, then the number of girls is :