If a team of $4$ persons is to be selected out of $4$ married couples to play a mixed doubles tennis game,then the number of ways of forming a team in which no married couple appears is:

An engineer is required to visit a factory for exactly $4$ days during the first $15$ days of every month,and it is mandatory that no two visits take place on consecutive days. The number of all possible ways in which such visits to the factory can be made by the engineer during $1-15$ June $2021$ is:

If ${}^{n-1}C_3 + {}^{n-1}C_4 > {}^{n}C_3$,then $n$ is just greater than which integer?

The total number of different combinations of one or more letters which can be made from the letters of the word $MISSISSIPPI$ is

In how many ways can $16$ rupees be divided among $4$ persons such that no person receives less than $3$ rupees?

$^{47}C_4 + \sum_{r=1}^5 {}^{52-r}C_3 = $