I forgot how to do that probability method that you would use in a question like you have a group of males and females in a line, and the females have to be separated by atleast one male. I can't remember distinctly, but it's like you would put the males down, and then use use combinations to determine where the females can sit. Thanks
Can someone please teach me this probability method? (1 Viewer)
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barbernator
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insertion method.
say the question was how many ways can we put 8 males and 5 females in a line, if no two females can be next to each other.
You place all the males in 8! ways. And then that leaves you with 9 spaces where the women can fit. So then you have 9P5 ways the women can be ordered in between the males.
hence the total ways of arranging is 8! x 9P5.
say the question was how many ways can we put 8 males and 5 females in a line, if no two females can be next to each other.
You place all the males in 8! ways. And then that leaves you with 9 spaces where the women can fit. So then you have 9P5 ways the women can be ordered in between the males.
hence the total ways of arranging is 8! x 9P5.
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RealiseNothing
what is that?It is Cowpea
Depends on whether or not what you are inserting is identical.
Capt Rifle
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So alternating, boy girl boy girl. Say there were 4 females, and 4 males. You need to arrange them in an alternate way so boy, girl, boy, girl. Now because you have four of each, it should look like this B G B G B G B G.
Do take note on how each girl has a boy next to her. Because there are four girl and four boys above we say 4! x 4! , because they can be rearranged. Also take note that B and G can switch positions so we multiply it again by 2!. Finally your answer should be 4! x 4! x 2!, which equals 1152.
Do take note on how each girl has a boy next to her. Because there are four girl and four boys above we say 4! x 4! , because they can be rearranged. Also take note that B and G can switch positions so we multiply it again by 2!. Finally your answer should be 4! x 4! x 2!, which equals 1152.