The number of ways in which $3$ children can distribute $10$ tickets out of $15$ consecutively numbered tickets themselves such that they get consecutive blocks of $5, 3 $ and $2$ tickets is
$^8C_5$
$^8C_5.3!$
$^8C_5.(3!)^2$
$^{15}{C_{10}}.3!$
A group consists of $4$ girls and $7$ boys. In how many ways can a team of $5$ members be selected if the team has at least one boy and one girl ?
The total number of ways of selecting six coins out of $20$ one rupee coins, $10$ fifty paise coins and $7$ twenty five paise coins is
The number of ways in which any four letters can be selected from the word ‘$CORGOO$’ is
In how many ways can a girl and a boy be selected from a group of $15$ boys and $8 $ girls
If $^{20}{C_{n + 2}}{ = ^n}{C_{16}}$, then the value of $n$ is