the number of ways Ms. Dutcher can choose groups of 4 from the 25 students in her 5th hour class.
(Hint: tell it wil permutation or a combination or nither)
2006-11-03 08:56:10 · 5 answers · asked by reaful 2 in Science & Mathematics ➔ Mathematics
25 ways for the first student in the group
24 ways for the 2nd student
23 ways for the 3rd student
22 ways for the 4th student
But order in the group doesn't matter, so you need to divide by the ways to arrange 4 people. This is 4! or 24.
This is the formula for "25 choose 4"
25 x 24 x 23 x 22 / 24
= 12,650 ways to choose groups of 4 from 25 students
2006-11-03 08:59:23 · answer #1 · answered by Puzzling 7 · 2⤊ 0⤋
Permutation because the 5 has nothing to do with the equation
25 x 24 x 23 x 22 x 21 x 20 x 19 x 18 x 17 x 16 x 15 x 14 x 13 x 12 x 11 x 10 x 9 x 8 x 7 x 6 x 5 divided by one
= 6.463004185 to the 23 power
2006-11-03 18:41:13 · answer #2 · answered by Waterfall 2 · 0⤊ 0⤋
This is a combination. you have 25 students and you want to choose group of 4
nCr(25,4) = 25!/(4!(25-4)!)
good luck
2006-11-03 17:54:43 · answer #3 · answered by rachie_grl6 2 · 0⤊ 0⤋
Answerer 2 (Puzzling) is right, so give the points there.
2006-11-03 17:02:14 · answer #4 · answered by Hy 7 · 0⤊ 0⤋
25x24x23x22 (hope you got a calculator)
2006-11-03 16:59:13 · answer #5 · answered by qrious 2 · 0⤊ 0⤋