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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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(11)

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Arpita kaushal

4 months ago

👍👍

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Akhilesh Pimparkhedkar

8 days ago

sir in second question.... we can directly do 6*6! / 3!2!.....cann't we?

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Ramita

9 months ago

i didn't quiet understand the 1st question can you please help me?

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χტ ϟ PαϻThεSϼαϻ420

8 months ago

We are basically calculating sum of individual digits of every number possible at every single position (ones, tens etc.) one by one and then multiplying it with its respective digits place and adding it up. This was only possible because, let's say at *ones* position every digit out (0,1,2,3) appears equal no. of times.

χტ ϟ PαϻThεSϼαϻ420

8 months ago

every digit out of*

Ishaan jain

8 months ago

Thnx

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Rupesh

2 months ago

the sum is clear...but forming a four digit number from 0,1,2,3 would be in 3*3*2*1 ways...coz the number of digits are just four and repetition can't be allowed

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Rupesh

2 months ago

the sum is clear...but forming a four digit number from 0,1,2,3 would be in 3*3*2*1 ways...coz the number of digits are just four and repetition can't be allowed

R

Rupesh

2 months ago

the sum is clear...but forming a four digit number from 0,1,2,3 would be in 3*3*2*1 ways...coz the number of digits are just four and repetition can't be allowed

Nishant Kr

10 months ago

10 lakhs wala question samajh nhi aaya sir !!

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Abantika Karmakar

a year ago

The total number of ways of doing this is 4!*5! = 2880. By placing the boys first by fixing one and arranging the rest of the girls.

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Sachin Rana

a year ago

Correct. Good.

Sagar Singh

7 months ago

288

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Sagar Singh

7 months ago

2880

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