XXX Solution
Integers XXX 15 XXX X
XX XXX XXX XXXXXXXX number of XXXXXX, XX get both XXX XXXXXX XX 15 XXX 6 then we check the greatest XXXXXX XXXXXX XX XXXX the XXXXXXX.
Factors of 6=X, X,X
Factor XX 15=1, 5,X
Hence XXX Gcf of both XX XXX 6 is 1x3= X
Thus 3 is the XXXXXXXX XXXXXX.