Probability Question 85

Question: Five coins whose faces are marked 2, 3 are tossed. The chance of obtaining a total of 12 is

[MP PET 2001; Pb. CET 2000]

Options:

A) $ \frac{1}{32} $

B) $ \frac{1}{16} $

C) $ \frac{3}{16} $

D) $ \frac{5}{16} $

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Answer:

Correct Answer: D

Solution:

Condition for sum of 12 is 2, 2, 2, 3, 3
$ \therefore $ Required probability $ ={{}^{5}}C_3{{( \frac{1}{2} )}^{3}}{{( \frac{1}{2} )}^{2}} $

$ =10.\frac{1}{2^{5}}=\frac{5}{16}. $