If the six numbers are all different, then the answer is 6C4 = 6*5/(2*1) = 15
If the order of the 4 numbers matters, then there are (6 x 5 x 4 x 3) = 360 .If the order of the 4 numbers doesn't matter, then there are 15 different groups of 4.
There are 6 groups.
2 groups
6 Groups Of 4 are in 24.
There are six (6) groups of 2 in three groups of 4. Your answer is six (6)
5
There are 28C6 = (28*27*26*25*24*23)/(6*5*4*3*2*1) = 376,740 sets.
24/4 = 6 groups
6 different groupings can be made from 12: 12 groups of 1, 6 groups of 2, 4 groups of 3, 3 groups of 4, 2 groups of 6, 1 group of 12.
There are 16 4-digit numbers that can be made up from 9 and 6.
from the numbers 4567 we can have 24 numbers
6! = 720