Question

For how many year did the writer know his grand mother

Answer 1

Answer:

I presume this question Is from the chapter "A Photograph" by Khushwant Singh.

Here's the answer :

The author says that, for the twenty years he had known his grandmother, she had always been old and wrinkled, so terribly old, that she couldn't get any older and had remained the same, all these years.

From this mention, we know that the author had known is grandma for 20 years.