Jan |
Feb |
March |
April |
May |
June |
July |
August |
September |
October |
November |
December |
${\color{DarkRed} S}$ |
${\color{DarkRed} S}$ |
${\color{DarkRed} S}$ |
${\color{DarkRed} S}$ |
${\color{DarkRed} S}$ |
${\color{DarkRed} S}$ |
${\color{DarkRed} S}$ |
${\color{DarkRed} S}$ |
${\color{DarkRed} S}$ |
${\color{DarkRed} S}$ |
${\color{DarkRed} S}$ |
${\color{DarkRed} S}$ |
${\color{DarkOrange} S}$ |
${\color{DarkOrange} S}$ |
${\color{DarkOrange} S}$ |
${\color{DarkOrange} S}$ |
${\color{DarkOrange} S}$ |
${\color{DarkOrange} S}$ |
${\color{DarkOrange} S}$ |
${\color{DarkOrange} S}$ |
${\color{DarkOrange} S}$ |
${\color{DarkOrange} S}$ |
${\color{DarkOrange} S}$ |
${\color{DarkOrange} S}$ |
${\color{Green} S}$ |
${\color{Green} S}$ |
${\color{Green} S}$ |
${\color{Green} S}$ |
${\color{Green} S}$ |
${\color{Green} S}$ |
${\color{Green} S}$ |
${\color{Green} S}$ |
${\color{Green} S}$ |
${\color{Green} S}$ |
${\color{Green} S}$ |
${\color{Green} S}$ |
${\color{Magenta} S}$ |
${\color{Magenta} S}$ |
${\color{Magenta} S}$ |
${\color{Magenta} S}$ |
${\color{Magenta} S}$ |
${\color{Magenta} S}$ |
${\color{Magenta} S}$ |
${\color{Magenta} S}$ |
${\color{Magenta} S}$ |
${\color{Magenta} S}$ |
${\color{Magenta} S}$ |
${\color{Magenta} S}$ |
Procedure:-
Select $12$ students and then put them in slots of $1^{st}$ row each like $1^{st}$ in jan, $2^{nd}$ in feb ,$3^{rd}$ in march and so on.
Repeat the above step $4$ times.
so Total students selected till now $= 12*4 =48$ and in each month we have $4$ students.
now if we select $1$ more student then his birthday can be in any of the given $12$ months.
say his birthday is in December then we can make a team of $5$ students such that
the members of the team must have birthdays in the same month.
$\therefore$ Total students required $= 48+1 =49.$