There are 210 ways to choose 4 persons from a group of 10.
The formula for "10 choose 4" is:
10! / (4! x 6!)
= (10 x 9 x 8 x 7) / (4 x 3 x 2 x 1)
= 5040 / 24
= 210
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
Well, honey, there are 30 students in the class, and you want to choose a group of 3. So, you're looking at a classic combination situation. The formula for combinations is nCr = n! / r!(n-r)!, so in this case, it's 30C3 = 30! / 3!(30-3)! = 4060 ways to choose those 3 lucky students. It's like picking the winning lottery numbers, but with fewer tears and more math.
it is a combination: 9!/4!=9 x 8 x 7 x 6
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
The answer is 15 * 14 * 13 = 15 P 3 = 780 IF you assume that no one person can hold two offices at once and that all in the group are qualified for any office.
There are 9*8*7 = 504 ways.