it is a combination: 9!/4!=9 x 8 x 7 x 6
40 x 39 x 38 x 37 = 2193360
You can arrange the letters in group One hundred and twenty-five different ways.
There are 9*8*7 = 504 ways.
-6
It is: 15C7 = 6435 combinations
3 students can be chosen from a class of 30 in (30 x 29 x 28) = 24,360 ways.But each group of the same 3 students will be chosen in six different ways.The number of different groups of 3 is 24,360/6 = 4,060 .
it is a combination: 9!/4!=9 x 8 x 7 x 6
40 x 39 x 38 x 37 = 2193360
The formula would be: (40!/36!)/4! This gives 2193360/24, or 91,390 unique groups.
10
I'm going with 25,200 3 men out of 10 may be chosen in 10C3 ways = 10 ! / 3! 7 ! = 120 ways. 4 women may be chosen out of 10 in 10C4 = 10 ! / 4! 6! ways = 210 ways. Therefore, a committee with 3 men and 4 women can be formed in 120 x 210 = 25,200 ways.
There are 11880 ways.
20C2 = 190
*facepalms* "Can you please repeat the question?"
125
You can arrange the letters in group One hundred and twenty-five different ways.