If two A.P.’ s are 2,5,8,11....... $T_{60}$ and 3, 5, 7, 9, ....., $T_{50}$, then the number of terms which are identical is 

$2,5,8,11,\mathrm{........}$

$a=2,d=3$

$T_{60}=2+(60-1)3=179$

$3,5,7,9,\mathrm{.......}$

$a=3,d=2$

$T_{50}=3+(50-1)2=101$

$5,11,17,\mathrm{......101}$

$\therefore$ number of terms are identical is 5, 11, 17, .., 101

$101=5+(n-1)6\Rightarrow 96=(n-1)6\Rightarrow n=17$