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# There are 10 cinema tickets with seat number from 1 to 10 in a row. Ram and Shyam are friends and they do not want to be apart. If they are asked to randomly pick up their tickets, what is the probability for Ram and Shyam to sit next to each other?

The total number of choice is $P_{2,10} = 90.$
If they are to be sit together, the answer is $2 \times 9 = 18$
So the probability is $\large \frac{18}{90}$$= \large\frac{1}{5}$.