There are total of 5 people (including martha). If martha sits in the middle, total people left to be arranged in a line are 4, who can arrange themselves in 4! ways.
Martha invited 4 friends to go with her to the movies. There are 120 different ways in which they can sit together in a row. In how many of those ways is Martha sitting in the middle?
How to solve this ?
I'm waiting for your replies,
Ok, see: martha and four of her friends go to a movie.Originally Posted by nihar
no of people: 5
total number of arrangements possible: 5! = 5*4*3*2*1 = 120
As there are totally five positions martha can occupy, the probability that martha will be in the middle is 1/5 and the number of arrangements in which this occurs is 1/5 * 120 = 24.
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