13 out of 45
Ravi correctly remember that he had gone to Delhi before October but after May but his brother correctly remember that he had gone Delhi July but before November. His father correctly remembers that the month in which he had gone was30 day month. In which month Ravi definitely gone.
|D||Cannot be determine|
|E||None of these|
Ans. A from Ravi = June, July, Aug, Sep
From his brother = Aug, Sep, Oct
Common factor = Aug, Sep
From his father Sep because it is 30 day month