Who overhears george telling lennie about their "dream" of having a place of their own?

Candy overhears and convinces George and Lennie to let him in on the plan because he has money for a down payment. George excitedly believes that, with Candy's money, they can swing the payment for a ranch he knows of; he figures one more month of work will secure the rest of the money they need. He cautions Lennie and Candy not to tell anyone.

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