Question

Question #dded5

Answer 1

`"No. of novel"=3`

`"No. of books of poem"=4`

`"No. of dictionary"=1`

`"Total No. of books"=3+4+1=8`

(i)
3 books can be chosen from total 8 books in `""^8C_3` ways.Keeping dictionary a fixed choice other 2 books can be chosen from rest 7 books in `""^7C_2` ways.

Hence the probability that among the three chosen book one is the dictionary,is `(""^7C_2)/(""^8C_3)=21/56=3/8`

(ii)
Amongst the 3 books chosen there wii be 1 novel and 2 books of poem.This can be done in `""^3C_1 xx""^4C_2` ways.
So the probability of this choice will be `(""^3C_1 xx""^4C_2) /(""^8C_3)=(3*6)/56=9/28`