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Grade 11Algebra

The number of ways in which we can n+p things into two groups is given by:-

(n+p)!/n!p!

if n=p then in books it is written number of ways become

(2n)!/n!n!2!

why additional 2! can someone explain, PLZ?

Profile image of Abhinav Saini
14 Years agoGrade 11
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1 Answer

Profile image of SOHAN  SARANGI
14 Years ago

Becoz when two similar type of objects are taken we have to divide by 2!.So here also we have n+n typesm of objects and so we have divide by 2!