Can You Manofy Your Girlfriend?

Your girlfriend is angry with you and so you wish to buy her a rose. You already have $3, but need $12 for a rose.

You play the following gambling game. Each round costs $1, and you have an equal chance of winning or losing. If you lose, you do not get anything (net -$1), and if you win, you get $2 (net +$1).

What is the probability that you will get $12 which would allow you to buy a rose to manofy your girlfriend?

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