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## Sachin Rana is teaching live on Unacademy Plus

Sachin Rana

IVth Year UG, IIT Bombay | YouTuber (143k subs) | Mentored 3 under 100 ranks in JEE Advanced | No. 1 educator for Organic Chemistry

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Nadeem rab

8 days ago

thanks sir for the lessons

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Sathya Praneeth Chamala

6 months ago

can any one explain me the ques of hw in last video which is explained in this video

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Naman Jolly

a year ago

For those who are confused how in the second question A intersection B is 96... here's how... see make a block of Britishers and Americans .. treat them both as 1 and 1 .. now total number of people would be 5 including the 2 from the blocks ... now number of ways would be { cause it is a circular permutation (n-1)! } (5-1)! × 2! × 2! that turns out to be 96 .. :)

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Rohit Yadav

7 months ago

for those who are still confused.. first two factorial is for Americans as a whole and British as sa whole arranging and the second one is for their interrnal arranggement

Abhinay Kumar

8 months ago

A intersection B = 4! x 2! x 2! = 96..REASON ---- this is the case when 2 American and 2 British take as 1 Now we have 5 people they sit on round table we take (5-1)! , 2! for arranging 2 Americans similarly for Britishers

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Vishal kumar

6 months ago

5026 HW answer

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Nabeel Khan

10 months ago

how did you get a intersection b in the nationality question
if possible tell me my mistake too
we can consider the group of Dutch and britishers to sit together that we consider them to be a single quantity and number of ways to arrange them with the others is 2! and now the people inside of this quantity can be arranged in 2! number of ways hence 4

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