In how many ways can 3 red and 4 black balls be arranged in a row?

In how many ways can 7 red and 6 black balls be arranged in a row, if no two black balls are together?

In how many ways can 12 white and 8 black balls be arranged in a row if no two black balls are together?

IN how mny ways can 18 white and 19 black balls be arranged in a row so that no two white balls may be together? It is given that balls ofteh same colour are identical.

IN how mny ways can 18 white and 19 black balls be arranged in a row so that no two white balls may be together? It is given that balls ofteh same colour are identical.

In how many ways can 4 boys and 3 girls be arranged in a row so that no two girls come together ?

how many ways can 3 boys and 4 girls be arranged in a row so that all the three boys are together?