Let S = {1,2,3,4,5} (a) List all the 3-permutations of S (a) List all the 3-combinations of S Can any one help me with this ??
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Originally Posted by bhuvan Let S = {1,2,3,4,5} (a) List all the 3-permutations of S (a) List all the 3-combinations of S Can any one help me with this ?? a) 5C3 = 5!/(3!*(5-3)!) = 10 (order doesn't matter) b) 5P3 = 5!/(5-3)! = 60 (order matters) a) {1,2,3} {1,2,4} {1,2,5} {1,3,4} {1,3,5} {1,4,5} {2,3,4} {2,3,5} {2,4,5} {3,4,5} Total = 10 b) {1,2,3} 124 125 132 134 135 142 143 145 152 153 154 . . . should add up to 60
Hello, bhuvan! Let (a) List all the 3-permutations of There are of them. I'll start the list . . . . . (b) List all the 3-combinations of There are of them . . . . . . Edit: . Ha! TitaniumX beat me to it . . . .
thank you very much ... How many solutions are there to the equation x1+x2+x3+x4=17 where x1,x2,x3 and x4 are nonnegative integers ?? appreciate your reply.
Originally Posted by bhuvan How many solutions are there to the equation x1+x2+x3+x4=17. where x1,x2,x3 and x4 are nonnegative integers ?? The number of ways to put N identical ones into k different variables (non-negative integers) is . Here N=17 and k=?
can you please give me one example of that ??
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