Set Breaker # 9 : Piece of cake

The Setup
You attend a school fete and enter a raffle for a handsome prize. The winner will be the person who most accurately estimates the retail price of a piece of cake. You think the slice is worth at least R10. As luck would have it, very few people attend the fete and the contest is between yourself and one other person. You wisely elect to go second. After the first entrant has stated that the value is R6, would your best answer be R9, R10 or R11?

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