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![There are 40 students in our class. How many ways they can be lined up such that two fixed
students X and Y are next to each other (order of the two fixed students does not matter).
Solution
So now that X and Y are always beside each other, then you can treat them as just ONE
PERSON.
Thus, it's like there are now just 39 people to permute.
As n! = number of ways to permute n objects in a line, then the number of ways is
#ways = 39! = 2.03979*10^46 [ANSWER]](https://image.slidesharecdn.com/thereare40studentsinourclass-230703180838-d7f21339/75/There-are-40-students-in-our-class-How-many-ways-they-can-be-lined-pdf-1-2048.jpg)
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There are 40 students in our class. How many ways they can be lined .pdf
In a class of 40 students, the number of ways to line them up with two fixed students, x and y, adjacent to each other is calculated by treating x and y as a single unit. This results in 39 units to permute, leading to a total of 39! arrangements. The final answer for the number of ways is approximately 2.03979 x 10^46.
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There are 40 students in our class. How many ways they can be lined .pdf
- 1. There are 40students in our class. How many ways they can be lined up such that two fixed students X and Y are next to each other (order of the two fixed students does not matter). Solution So now that X and Y are always beside each other, then you can treat them as just ONE PERSON. Thus, it's like there are now just 39 people to permute. As n! = number of ways to permute n objects in a line, then the number of ways is #ways = 39! = 2.03979*10^46 [ANSWER]