Question 396177
a) 

no. of ways to arrange 5 persons if no restrictions = 5! = 120



b) 
no. of ways to arrange 3 boys together = 3! = 6

no. of ways to arrange 2 girls together= 2! = 2


no. of ways to arrange boys and girls together in a row = 6 * 2 * 2 = 24
( as group of boys and group of girls can also arrange by 2 ways )





C)
no. of ways when 2 girls are together = 4! * 2! = 48
(assume 2 girls as a single person, then total 4 persons)




d)
no. of ways when Rachel and Jonathan are together = 4! * 2! = 48


 no. of ways when both are not together =  total no. of ways  - 48 

= 120 - 48 

= 72 




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