Question

A letter is known to have come either from London and Clifton. On the postmark only the two consecutive letters ON are eligible. What is the change that it came from London?

Answer 1

The 2 places are LONDON- ON and CLIFTON-ON

So, ON occurs 2 times and 1 time in the names respectively

So, probability that it came from london $=\frac{2}{2+1}=\frac{2}{3}$