In an interview I was asked the below puzzle as the last question:

A person goes to a shop to buy something and the ensuing conversation with the shopkeeper is mentioned below...

Person: How much does one cost?
Shopkeeper: It is Rs10.
Person: How much for 14?
Shopkeeper: Rs20.
Person: How much for 114?
Shopkeeper: Rs30.

What is the person trying to buy?

I couldn't answer. Still figuring it out.


1 Answer 1


This is a classic puzzle. I was so sure that it must already have been asked here on Puzzling, but I have been unable to find a duplicate after a short keyword search (this question is perhaps the closest...). The answer is:

house numbers (i.e. the usually metallic numerals that can be mounted on a wall or fence to indicate the house number). Usually, these are costed at a certain price per digit - in the case of your question, Rs10 for a single digit.

House numbers

This way, one numeral (e.g. for a house numbered 1-9) costs Rs10. But the two numerals required for a house numbered '14' would cost Rs20 (2 times Rs10, for a 1 and a 4) and the total cost of three numerals for a house numbered '114' would be Rs30 (3 times Rs10, for two 1s and a 4).


Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.