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## Sachin Rana is teaching live on Unacademy Plus

Sachin Rana

IVth Year UG, IIT Bombay | YouTuber (150k subs) | No. 1 educator for Organic Chemistry.

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(11)

U

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Cse Aspirant

2 years ago

HERE IS ANOTHER AWESOME LESSON FROM THE PUREST OF THE PURE SOUL ON THIS PLANET EARTH.....LONG LIVE ROMAN SIR...AND LONG LIVE UNACADEMY TEAM.... FEELING BLESSED TO BE BORN IN ''ROMAN ERA''....THANK U IS NOT THE WORD...SALUTE TO ALL MOTERS OF FOUNDING FATHERS AND GREAT EDUCATORS AND OTHER CONTRIBUTORS OF UNACADEMY...

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Akhilesh Pimparkhedkar

2 months ago

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

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Ramita

a year ago

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

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χტ ϟ PαϻThεSϼαϻ420

10 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

10 months ago

every digit out of*

Ishaan jain

10 months ago

Thnx

R

Rupesh

4 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

4 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

4 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

a year 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

8 months ago

288

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Sagar Singh

8 months ago

2880

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