(adsbygoogle = window.adsbygoogle || []).push({}); 1.Marina Lobo wrote 10 novels, 5 f which occupy one volume and the other 5 occupy two volumes each. A person checks out 5 volumes from Marina Lobo's shelf at random. The library holds exactly one copy of each of her novels.

(a) Show that for any i=1,2,3,4,5 the probability that the ith single volume novel checked out is1/3.

(b) Show that any i= 1,2,3,4,5 the probability that the ith two volume novel checked out is 2/21.

3. I approached part a by saying that there are 5 single volume novels and there are 15 volumes to choose from so 5/15=1/3. I thought it was correct to approach part b in the same way by saying there are 10C2 (because there are 5x2 two volume novels and we pick 2 to make up the complete novel)/15C5 because you have to choose 5 volumes from 15 which gives 15/1001 which is not 2/21!! I'm not sure how to approach this. Should I use generating functions to show this? Have I got part a wrong too and just got the correct answer by coincidence?

Any help and advice would be greatly appreciated, thank you.

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# Homework Help: Probability-Generating function- but I am not sure

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