Your best friend (Bob) comes to you with this problem.

The Problem

His teacher (Mr. Sam) will ask Bob to work out a number in a child (Joan) head from 1 and 27.
Bob has to find the correct number, by asking Joan three Yes/No questions about the number.
Joan can respond with 3 different answers: "Yes", "No", or "I do not know".

Joan is a smart boy, but he doesn't know about another base number except 10. So by asking that kind of question he will answer "I do not know"

Example:
If the number is 12

Is it an even number? Yes.
Is it divisible by 9? No.
If I take a random number between 10 to 15, will I get the right number? I do not know.

------------------

Another Example:
If the number is 9

Is it an even number? No.
Is it divisible by 9? Yes.
If I take a random number between 10 to 15, will I get the right number? No.

------------------

Find the strategy, so every number from 1 to 27 can be guessed correctly.

## Question

## jasen

Your best friend (Bob) comes to you with this problem.

The ProblemHis teacher (Mr. Sam) will ask Bob to work out a number in a child (Joan) head from 1 and 27.

Bob has to find the correct number, by asking Joan three Yes/No questions about the number.

Joan can respond with 3 different answers: "Yes", "No", or "I do not know".

Joan is a smart boy, but he doesn't know about another base number except 10. So by asking that kind of question he will answer "I do not know"

Example:If the number is 12

Is it an even number? Yes.

Is it divisible by 9? No.

If I take a random number between 10 to 15, will I get the right number? I do not know.

------------------

Another Example:If the number is 9

Is it an even number? No.

Is it divisible by 9? Yes.

If I take a random number between 10 to 15, will I get the right number? No.

------------------

Find the strategy, so every number from 1 to 27 can be guessed correctly.

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